The ecology of keratinophilic fungi at different depths of soil.

The influence of depth and humus content of soil, on the presence of keratinophilic fungi in 4 layers (1-10 cm, 11-25 cm, 26-40 cm, 41-55 cm) of carbonate meadow, chernozem carbonate meadow and carbonate alluvial soils was studied. Different keratinophilic fungi were found not only in individual soils but also in different layers of the same soil. The greatest number and quantity occurred in soil with highest humus content. These fungi were present in greatest amount in the superficial layers (1-10 cm and 11-25 cm) of all soils investigated.     

Impact of some ecological factors on the occurrence of poultry soil-inhabiting keratinophiles

Investigations were conducted to assess the ecological factors governing distribution and survival of keratinophilic fungi in poultry farm soils. All the poultry farm soils were rich in humus and the keratinophilic fungi were generally found to be proportional to the soil organic matter. These soils were nearly neutral to weakly alkaline and organically rich with a high content of organic carbon, nitrogen, phosphorus, potassium, magnesium, calcium and iron. This revised version was published online in June 2006 with corrections to the Cover Date.     

Investigation of keratinophilic fungi from soils in Western Australia a preliminary survey

In order to determine which species of geophilic dermatophytes were present in Western Australian soils 299 samples were investigated. These samples were collected from a range of locations, 208 from towns throughout the state and 91 samples from the Perth Metropolitan area.Most samples were collected from areas frequented by people and animals, such as home gardens, parks and animal yards.Of the total 299 soils, 271 (90.6 %) yielded keratinophilic fungi. A total of 181 dermatophytes were isolated, and there were 205 isolations of other keratinophilic fungi. Microsporum gypseum (30.7 %) was the most prevalent dermatophyte recovered from soil followed byMicrosporum cookei (21.7 %) and thenTrichophyton ajelloi (8.0 %). No other dermatophytes were recovered.Chrysosporium indicum was the most common of all the keratinophilic fungi and was isolated from 50.1 % of the samples. Mixed growth was obtained from 33.5 % of the soil samples.     

Hongos queratinofílicos en suelos de parques de la ciudad de Corrientes,Argentina

BackgroundThe soil is a natural reservoir of keratinophilic fungi, which are a small but important group of filamentous fungi, some of which typically develop on keratinized tissues of living animals. There are numerous species of saprophytic fungi with recognized keratinophilic abilities, and several studies have been undertaken in order to link their presence to possible human disease.AimsTo know the biota of geophilic fungi in general and of keratinophilic fungi particularly in soils from two public parks.MethodsSoil samples from two public parks of Corrientes city, Argentina, were studied during two seasons, using the hook technique and serial dilutions for fungal isolation.ResultsUsing the hook technique, 170 isolates were classified into 17 genera and 21 species, among which it is worth mentioning the presence of Microsporum canis. Shannon index for keratinophilic fungi in autumn was 2.27, and 1.92 in spring. By means of the serial dilutions technique, 278 fungi isolated were identified into 33 genera and 71 species. Shannon index in autumn was 3.9, and 3.5 in spring.ConclusionsThe soils studied have particularly favorable conditions for the survival of pathogens and opportunistic geophilic fungi for humans and animals.     

Diversity of keratinophilic mycoflora in the soil of Agra (India)

Diversity of keratinophilic mycoflora in the soil of Agra was under observation for 1 year (July 2001-June 2002) and isolation of keratinophilic fungi was followed by the hair-baiting method. The frequency of occurrence of keratinophilic fungi in 284 soil samples collected from various hospitals, cattle yards, poultry farms, crop fields and playgrounds was determined, 204 samples (72%) having been found to be positive. A total of 33 species classified into 11 genera (Acremonium, Aspergillus, Chrysosporium, Emmonsia, Geomyces, Keratinophyton, Microsporum, Myceliophthora, Penicillium, Sporotrichum, Trichophyton) were encountered from the soil samples. Sporotrichum spp. were found to be the most dominant species followed by Trichophyton simii. The parameter of keratinophilic fungi found in the samples studied ranged from 62 to 80% where playgrounds yielded the maximum number of species (80%) while the least dominating soil was hospital soil (62%). Among all the baits used maximum fungi occurred on human hairs (82%) followed by chicken feather (74%), wool (61%) and the least on horns (45%). The spectrum of keratinophilic fungi isolated from different sites differed considerably according to the frequency of use by humans.     

Keratinophilic fungi from urban soils of Barcelona,Spain

Fifty soil samples of urban soils of Barcelona (Spain) were analyzed. We isolated the following keratinophilic fungi: Trichophyton ajelloi, Microsporum gypseum, Chrysosporium keratinophilum, C. evolceanui, C. tropicum, C. indicum and C. asperatum.     

Growth Characteristics and Enzyme Activity in Batrachochytrium dendrobatidis Isolates

Eighty soil samples were collected from various sites of Bahrain and screened for presence of keratinophilic fungi using hair baiting techniques for isolation. Thirty-six isolates were recovered and identified. The cultures were identified using macro- and micromorphological features. Their identification was also confirmed by the BLAST search of sequences of ITS1-5.8S-ITS2 rDNA region against the NCBI/Gene bank data and compared with deposited sequences for confirmation. Eight species of five genera were isolated viz. Aphanoascus fulvuscence (8.75%), Aphanoascus punsolae (20.00%), Chrysosporium indicum (2.50%), Chrysosporium tropicum (2.50%), Chrysosporium zonatum (3.75%), Spiromastix warcupii (1.25%), Microsporum gypseum (3.75%), and Trichophyton mentagrophytes (2.50%). In conclusion, our study indicates that keratinophilic fungi do occur in the various soils of Bahrain. Moreover, the narrow diversity and low density of keratinophilic fungi in the investigated soils is expected and is emblematic to other hot arid environments.     

Generalist entomopathogens as biological indicators of deforestation and agricultural land use impacts on Waikato soils

The relative abundance of entomopathogenic nematodes and fungi was estimated for 10 sites in each of indigenous forest, pasture, and cropland habitats by baiting soil samples with Galleria larvae. The steinernematid Steinernema feltiae (Filip) was the dominant nematode, occurring in soils from all three habitat types. The heterorhabditid Heterorhabditis zelandica Poinar was recovered only from soils of podocarp (Dacrycarpus dacrydioides (A. Rich.)) forests. Galleria infection by nematodes was higher in soils from forest habitat than in soils from pasture and cropland. Among the sampled forests, nematode infection was higher in soils from podocarp stands than those from broadleaf stands. The deuteromycete fungi Beauveria bassiana (Balsamo) Vuillemin, Metarhizium anisopliae (Metschnikoff) Sorokin, and Paecilomyces cf. cicadae (Miquel) Samson, and a Entomophthorales zygomycete, tentatively identified as a Tarchium species, were recovered from the Galleria baits. Infection of Galleria by B. bassiana and M. anisopliae occurred in soils from all habitat types, while that by P. cicadae occurred only in soils from forest habitats. Tarchium was recovered from a single pasture site. The frequency of Galleria infection by these entomopathogenic fungi collectively, and by B. bassiana alone, was higher in pasture soils than in soils from either forest or cropland. These results are discussed in relation to disturbance effects of land use changes and the potential role of generalist entomopathogens as biological indicators of soil health.     

Evidence for different contributions of archaea and bacteria to the ammonia-oxidizing potential of diverse Oregon soils

A method was developed to determine the contributions of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) to the nitrification potentials (NPs) of soils taken from forest, pasture, cropped, and fallowed (19 years) lands. Soil slurries were exposed to acetylene to irreversibly inactivate ammonia monooxygenase, and upon the removal of acetylene, the recovery of nitrification potential (RNP) was monitored in the presence and absence of bacterial or eukaryotic protein synthesis inhibitors. For unknown reasons, and despite measureable NPs, RNP did not occur consistently in forest soil samples; however, pasture, cropped, and fallowed soil RNPs commenced after lags that ranged from 12 to 30 h after acetylene removal. Cropped soil RNP was completely prevented by the bacterial protein synthesis inhibitor kanamycin (800 μg/ml), whereas a combination of kanamycin plus gentamicin (800 μg/ml each) only partially prevented the RNP (60%) of fallowed soils. Pasture soil RNP was completely insensitive to either kanamycin, gentamicin, or a combination of the two. Unlike cropped soil, pasture and fallowed soil RNPs occurred at both 30°C and 40°C and without supplemental NH(4)(+) (≤ 10 μM NH(4)(+) in solution), and pasture soil RNP demonstrated ～ 50% insensitivity to 100 μM allyl thiourea (ATU). In addition, fallowed and pasture soil RNPs were insensitive to the fungal inhibitors nystatin and azoxystrobin. This combination of properties suggests that neither fungi nor AOB contributed to pasture soil RNP and that AOA were responsible for the RNP of the pasture soils. Both AOA and AOB may contribute to RNP in fallowed soil, while RNP in cropped soils was dominated by AOB.     

Keratinolytic fungi of wadi Qena in Egypt

Forty-six soil samples collected from different sites of wadi Qena were examined for keratinophilic fungi using the hair baiting technique. Thirty-two species in addition to one variety of each ofA. nidulans andA. flavus which belong to eighteen genera were recovered.Aspergillus, Chrysosporium, Penicillium, Microsporum andFusarium were the most frequent genera developed from baited soils.     

Survey of keratinophilic fungi isolated from city park soils of Pisa,Italy

A survey of geophilic dermatophytes and related keratinophilic fungi isolated from city park soils of Pisa is reported. Twenty-three (48%) soil samples out of 48 were positive by hair baiting. The following species were isolated: Microsporum gypseum (39%), Trichophyton ajelloi (31%), Chrysosporium keratinophilum (14%), T. terrestre (8%), M. fulvum, Ch. luteum, Ch. indicum (5% each) and M. cookei (2%). The presence of the different species is discussed in relation to the risk of fungal skin infections. This revised version was published online in June 2006 with corrections to the Cover Date.     

Keratinophilic fungi from Nigerian soil

During a survey of keratinophilic fungi in Nigerian soil samples, twelve species of fungi were isolated. These included Chrysosporium keratinophilum, C. tropicum, Curvularia lunata, Microsporum audouinii, M. canis, M. fulvum, M. gypseum, M. vanbreuseghemii, Trichophyton ajelloi, T. mentagrophytes, T. soudanense and T. yaoundei. These keratinophilic fungi had a higher incidence by occurrence of individual species during the rainy season (May–October) than the dry season (November–April).     

Selection of efficient VA mycorrhizal fungi

Summary A procedure is described for selection and screening of VA mycorrhizal fungi in pot and field trials. The VA mycorrhizal fungi from 20 farm paddocks with unexpectedly high pasture production were compared withGlomus fasciculatus for ability to stimulate plant growth. The fungi from three soils (F4, F11, and F20) which were 84–142% more effective thanG. fasciculatus at stimulating growth in sterilised soils were then tested for ability to stimulate clover growth in unsterilised soils in pots, and in the field. F4, F11 and F20 were more efficient thanG. fasciculatus and the indigenous mycorrhizal fungi in all except one field soil.     

The isolation of histoplasma duboisii and keratinophilic fungi from soils of east africa

Summary Isolation ofHistoplasma duboisii marks the first incidence of this African pathogen being found in the soil of Kenya.Investigation of keratinophilic fungi in soil from Kenya and Tanzania produced 27 isolates of dermatophytes belonging to the four known genera of this group.Trichophyton evolceanui was found in five of these samples.It is to be noted that localities frequented by wild and domestic animals produced a higher incidence of keratinophilic fungi than did the unshady, isolated areas.     

Further studies of the keratinophilic fungi in African soils

Sixty-eight soil samples from Kenya and nine from South Africa were tested for their keratinophilic and systemic fungi. Also, 150 types of hair were tested to find which would produce the best results for isolating fungi from soil, using the hair-bating technique. Hair from mature male baboons was found to be superior over all others in trapping keratinophilic fungi from experimentally infested soil. Thirty-three isolates of keratinophilic fungi were obtained, withChrysosporium sp. the most frequently isolated fungus, followed byM. gypseum. Systemic pathogenic fungi were absent from samples taken in these studies, as ascertained by mouse inoculation. Furthermore, there was no significant correlation between the locality and the inhabitants, with either the number or the species of keratinophilic fungi isolated.

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Zusammenfassung Achtundsechzig Bodenproben von Kenya und von Südafrika wurden für keratinophile und System-Pilze untersucht. Auch 150 Haartypen wurden untersucht, um herauszufinden, welche die besten Ergebnisse für die Isolierung von Pilzen vom Boden mittels der ToKaVa Methode liefern würden. Haare der erwachsenen, männlichen Paviane waren bei weitem allen anderen Haaren überlegen für die Isolierung keratinophiler-Pilze vom Boden. Dreiunddreißig keratinophile Pilze sind isoliert worden, wobeiChrysosporium spp. die häufigsten waren.M. gypseum war das nächste. Systemische, pathogene Pilze waren in diesen Untersuchungen abwesend, wie es durch Mausimpfungen festgestellt wurde. Es gab auch keine bedeutende Korrelation zwischen Lokalität und Einwohnerschaft weder nach der Zahl noch nach der Art der isolierten, keratinophilen Pilze.

     

A preliminary study of marine fungi from Abaco Island,the Bahamas

Marine soil, mangrove wood, and free floating algal collections were made in the shallow littoral zone of Abaco Island, The Bahamas. Material was subsequently examined in the laboratory for fungal populations inhabiting seawater shorelines of the island. The study follows previous mycological investigations of Abaco including the keratinophilic fungi (10) and the fresh water fungi (11).     

Keratinophilic fungi of school playgrounds in the Nablus area,West Bank of Jordan

The distribution of keratinophilic fungi in the soil of 57 school playgrounds in the Nablus area was studied with relation to human presence. A total number of 73 species was recovered. Thirteen of these species were dermatophytes and closely related fungi. The most common and frequent species of the latter fungi were: Arthroderma cuniculi (found in 32.1% of school playgrounds), Chrysosporium keratinophilum (32.1%), Microsporum gypseum (10.7%), T. terrestre (7.1%), and C. asperatum (7.1%). Twenty eight of the isolated species had been reported to be pathogenic; these comprised 64.3% of the keratinophilic mycoflora of school playgrounds.     

The occurrence of keratinophilic fungi in texas soil

Summary A total of 137 soils, 27 coming from caves and 110 from outdoor lands of Texas, were examined for the presence of keratinophilic fungi by the use of the ToKaVa hairbaiting technique. Twenty three and 69 fungal isolates, respectively, were recovered from these areas. Microsporon gypseum was the most common isolate, followed byTrichophyton mentagrophytes, andT. terrestre. M. gypseum was recovered from caves in a very high frequency (67 %), in comparison to its presence in the outdoor soils (10 %).Fifteen strains ofChrysosporium, belonging to four species, were isolated. Fourteen of these isolates were recovered from shady areas under trees. None of these had been isolated from Texas soil before.     

The distribution of geophilic dermatophytes and other keratinophilic fungi in relation to the pH of the soil

Summary Keratinophilic fungi have been isolated from 178 (71.3 %) out of 250 soil samples taken from different sites in the surroundings of Berlin. The pH-values of the soils recorded vary within a range from 3.0 to 8.0. Most of the soils with the lowest pH (3.0–4.5) do not yield keratinophilic fungi while almost all of them with a pH higher than 5 do contain 1 to 6 kerationphilic species. The average pH of soils negative for these fungi is pH 4.1, the average pH of positive samples is 5.8. The distribution of individual species is also influenced by the pH of the soil. OnlyKerationmyces ajelloi is recovered in the same rate from soils with pH lower and higher than 6, the other species more frequently occur in weakly acid to weakly alkaline reacting soils. The development of keratinophilic and keratinolytic fungi generally seems to be favoured under nearly neutral to weakly alkaline conditions. A similar range of pH has proved to be the most favourable to several metabolic activities of these fungi. The pH-optima of enzymes excreted by dermatophytes have been found to be within this range. Enzyme activity is inhibited if the pH of the substrate decreases below 4.0. The absence of keratinophilic fungi in strongly acid soils may therefore be due to the inhibition of enzyme activities under these conditions.

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Zusammenfassung Aus 178 von 250 in der Umgebung von Berlin gesammelten Bodenproben wurden keratinophile Pilze isoliert (71,3%). Die untersuchten Böden wiesen pH-Werte zwischen 3,0 und 8,0 auf. Es bestanden enge Beziehungen zwischen dem pH-Wert des Bodens und dem Vorkommen keratinophiler Pilze. In den meisten Proben mit pH-Werten unter 4,5 fehlten diese Pilze, während in fast allen Proben mit pH-Werten über 5,0 mindestens eine, oft mehrere keratinophile Arten nebeneinander vorkamen. Der Durchschnitts-pH-Wert aller Proben, die keine keratinophilen Pilze aufwiesen, betrug 4,1, der entsprechende Wert für solche Pilze enthaltende Proben 5,8. Die einzelnen Arten zeigten eine unterschiedlich starke Bevorzugung der schwach sauer bis schwach alkalisch reagierenden Böden. NurKeratinomyces ajelloi war in Böden mit pH-Werten unter und über 6,0 gleichmäßig verteilt, während alle anderen Arten in fast neutralen Böden gehäuft auftraten. Wachstum und Stoffwechsel keratinophiler und keratinolytischer Pilze werden anscheinend grundsätzlich unter neutralen bis schwach alkalischen Bedingungen gefördert. Die pH-Optima von Dermatophyten ins Nährmedium ausgeschiedener Enzyme liegen auch in diesem Bereich. Sinkt der pH-Wert des Substrates unter pH 4,0, wird die Aktivität dieser Enzyme fast völlig unterbunden. Das Fehlen keratinophiler Pilze in stark sauren Böden läßt sich daher wahrscheinlich auf eine Hemmung iher für den Aufschluß des Keratins notwendigen Ektoenzyme zurückführen.

     

Keratinophilic fungi from Orissa, India, II: Isolations from feathers of wild birds and domestic fowls

Feather samples from 117 birds, representing 11 species, were examined for keratinophilic fungi. Of these, 63 (53.8%) were found to be positive. Nine species of fungi classified in 6 genera were isolated: Aphanoascus terreus (1.7%), Chrysosporium indicum (26.4%), Chrys. tropicum (11.1%) the Chrysosporium state of Aphanoascus spp. (2.5%), the Chrysosporium state of Arthroderma tuberculatum (3.4%), Ctenomyces serratus (0.8%), Gymnoascoideus petalosporus (7.6%), Malbranchea spp. (6.8%), Rollandina hyalinospora (6.8%). Passer domesticus (the house sparrow) harboured the largest varieties of keratinophilic fungi: the Chrysosporium state of Arthroderma tuberculatum was found to be associated with it selectively. The associations of these keratinophilic fungi with birds were non-clinical in nature.