Hongos queratinofílicos en suelos de parques de la ciudad de Corrientes, Argentina / Keratinophilic fungi in soils of parks of Corrientes city, Argentina

Antecedentes. El suelo es el reservorio natural de hongos queratinofílicos que constituyen un pequeño pero importante grupo de hongos filamentosos; algunos de ellos se desarrollan típicamente sobre tejidos queratinizados de animales vivos. Hay numerosas especies de geohongos saprobios con habilidades queratolíticas reconocidas y son varios los trabajos realizados con el fin de vincular su presencia a la posible enfermedad humana. Objetivos. Conocer la biota de geohongos en general y la de aquellos queratolíticos en particular en suelos de dos parques públicos. Métodos. Las muestras se tomaron de suelos de dos parques públicos de la ciudad de Corrientes, Argentina, durante dos estaciones del año. Para el aislamiento de los hongos se usaron las técnicas del anzuelo queratínico y la de las diluciones. Resultados. Mediante la técnica del anzuelo se aislaron 170 cepas que se clasificaron en 17 géneros y 21 especies, entre las que merece destacar la presencia de Microsporum canis. El índice de Shannon de hongos queratolíticos fue medio, siendo en otoño (2,27) más alto que en primavera (1,92). Con la técnica de diluciones seriadas se obtuvieron 278 cepas que se clasificaron en 33 géneros y 71 especies; el índice de Shannon fue más alto en otoño (3,9) que en primavera (3,5). Conclusiones. Los suelos estudiados presentan condiciones particularmente favorables para la supervivencia de geohongos patógenos y oportunistas para el hombre y los animales (AU)

Background. The 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. Aims. To know the biota of geophilic fungi in general and of keratinophilic fungi particularly in soils from two public parks. Methods. Soil samples from two public parks of Corrientes city, Argentina, were studied during two seasons, using the hook technique and serial dilutions for fungal isolation. Results. Using 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. Conclusions. The soils studied have particularly favorable conditions for the survival of pathogens and opportunistic geophilic fungi for humans and animals (AU)

[Keratinophilic fungi in soils of parks of Corrientes city, Argentina]. / Hongos queratinofílicos en suelos de parques de la ciudad de Corrientes, Argentina.

BACKGROUND: The 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. AIMS: To know the biota of geophilic fungi in general and of keratinophilic fungi particularly in soils from two public parks. METHODS: Soil samples from two public parks of Corrientes city, Argentina, were studied during two seasons, using the hook technique and serial dilutions for fungal isolation. RESULTS: Using 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. CONCLUSIONS: The soils studied have particularly favorable conditions for the survival of pathogens and opportunistic geophilic fungi for humans and animals.

Huevos de Toxocara canis como anzuelo para hongos geófilos en una ciudad subtropical / Toxocara canis eggs as bait for soil fungus in a subtropical city

Antecedentes. Las diferentes técnicas de aislamiento permiten recuperar hongos en función de su capacidad para utilizar o no un determinado sustrato. La técnica de espolvoreado es un método para la recuperación de hongos nematófagos del suelo. Estos hongos son predadores naturales de los nematodos y están ampliamente distribuidos en la naturaleza. Objetivos. Detectar hongos con posible capacidad nematófaga en suelos de parques de la ciudad de Corrientes (Argentina). Métodos. Las muestras de tierra fueron tomadas eligiendo al azar una zona del suelo entre dos árboles, desechando la hojarasca y a no más de 2 cm de profundidad. El aislamiento se realizó según la técnica de espolvoreado utilizando huevos de Toxocara canis como anzuelo. Resultados. Se recogieron 18 muestras de suelo, de las que se aislaron 6 géneros y 8 especies de hongos. El método del espolvoreado, simple y eficiente, tiene la ventaja de utilizar una pequeña cantidad de suelo sin tratamiento y permite aislar hongos que pueden crecer sobre huevos de geohelmintos. Este estudio permitió recuperar hongos de los géneros Bipolaris, Fusarium, Purpureocillium, Curvularia, Phoma y Scytalidium. Conclusiones. No se ha encontrado bibliografía de los géneros Curvularia, Phoma y Scytalidium que describa la interacción de estos hongos con huevos de nematodos y queda, por tanto, el desafío de investigar cuál es su verdadera acción sobre estos huevos (AU)

Background. The use of different isolation techniques allows the recovery of fungi based on their ability to use selective substrates. The sprinkle method is a technique for the recovery of nematophagous fungi in the soil. These fungi are natural predators of nematodes and are widely distributed in nature. Aims. To detect possible fungi with nematophagous ability in the soil of city parks in Corrientes (Argentina). Methods. The soil samples were taken from an area of ground between two trees and to no more than 2 cm deep. The isolation was performed according to the sprinkle method with Toxocara canis eggs as bait. Results. Eighteen soil samples were collected, and 6 genera and 8 species of fungi were isolated. The sprinkle method, simple and efficient, has the advantage of using a small amount of untreated soil for the isolation of fungi that can grow on the eggs of geohelminths. The genera Bipolaris, Fusarium, Purpureocillium, Curvularia, Phoma and Scytalidium were isolated in this study. Conclusions. No other studies describing the interaction between the genera Curvularia, Phoma and Scytalidium with nematode eggs have been found in the literature, thus more studies are required to determine what is their real action on these eggs (AU)

[Toxocara canis eggs as bait for soil fungus in a subtropical city]. / Huevos de Toxocara canis como anzuelo para hongos geófilos en una ciudad subtropical.

BACKGROUND: The use of different isolation techniques allows the recovery of fungi based on their ability to use selective substrates. The sprinkle method is a technique for the recovery of nematophagous fungi in the soil. These fungi are natural predators of nematodes and are widely distributed in nature. AIMS: To detect possible fungi with nematophagous ability in the soil of city parks in Corrientes (Argentina). METHODS: The soil samples were taken from an area of ground between two trees and to no more than 2cm deep. The isolation was performed according to the sprinkle method with Toxocara canis eggs as bait. RESULTS: Eighteen soil samples were collected, and 6 genera and 8 species of fungi were isolated. The sprinkle method, simple and efficient, has the advantage of using a small amount of untreated soil for the isolation of fungi that can grow on the eggs of geohelminths. The genera Bipolaris, Fusarium, Purpureocillium, Curvularia, Phoma and Scytalidium were isolated in this study. CONCLUSIONS: No other studies describing the interaction between the genera Curvularia, Phoma and Scytalidium with nematode eggs have been found in the literature, thus more studies are required to determine what is their real action on these eggs.