Onygenales (Eurotiomycetes, Ascomycota) queratinofílicos en suelos de establecimientos educacionales urbanos y rurales de la V Región, Chile / Queratinophilic onygenales (Eurotiomycetes, Ascomycota) in urban and rural soils of eduacational center of V Region, Chile

Con la finalidad de estudiar la presencia de Onygenales queratinofílicas potencialmente patógenas para el hombre y los animales, se analizaron mediante la técnica del anzuelo queratínico (Marzo – Diciembre, 2006), suelos de establecimientos educacionales urbanos y rurales de la V Región, Chile. Se colectaron un total de 64 muestras, de las cuales, la mitad se obtuvieron en Valparaíso-Viña del Mar (urbano) y la otra en Olmué-Limache (en zonas rurales). En zona urbana se aislaron 112 cepas (7 géneros y 12 especies) y en la rural 147 (11 géneros y 18 especies). Los géneros de mayor prevalencia en la zona urbana y rural en orden decreciente fueron: Chrysosporium y su teleomorfo 32 por ciento versus 45 por ciento; Keratinomyces y su teleomorfo, 26 por ciento y 16 por ciento; Microsporum y su teleomorfo 23 por ciento y 16 por ciento y Myceliophthora y su teleomorfo con un 13 y 10 por ciento. Amauroascus mutatus, Auxarthron umbrinum, Gymnoascus reessii, Chrysosporium charmichaelii, Ch. merdarium, Ch. tropicum, Geomyces pannorum var. pannorum fueron detectados sólo en la zona rural; mientras que Malbranchea flava sólo en la zona urbana. Mediante la técnica de Takashio, se pudo identificar separadamente las especies del complex Microsporum gypseum, determinándose que M. gypseum (Arthrodema gypseum) y M.fulvum (A. fulvum) obtuvieron una frecuencia de aislamiento similar en ambas zonas, siendo el primero un oportunista potencialmente patógeno para el hombre y los animales.

With the purpose of studying the presence of keratinophilic Onygenales that are potentially pathogenous for man and animal, urban and rural soils from educational centers in the V Region were examined with the keratinic bait technique (march-december 2006). A total of 64 samples were collected, 32 of them being from Valparaíso-Viña del Mar (urban) while the rest in Olmué-Limache (in rural zones). One hundred and twelve strains (7 genera and 12 species) were collected in the urban zone and 147 strains in the rural zone (11genera and 18 species). Genera with the highest prevalence both in the urban and the rural zones were, in decreasing order: Chrysosporium and its teleomorph 32 per cent vs. 45 per cent; Keratinomyces and its teleomorph 26 per cent and 16 per cent; Microsporum and its teleomorph 23 per cent and 16 per cent and Myceliophthora and its. teleomorph with 13 per cent and 10 per cent. Amauroascus mutatus, Auxarthron umbrinum, Gymnoascus reessii, Chrysosporium charmichaelii, Ch. merdarium, Ch.tropicum, Geomyces pannorum var. pannorum were detected only in the rural zone, whereas Malbranchea flava only in the urban zone. Species of the complex Microsporum gypseum, could be identified separately by means of the Takashio technique, coming to the conclusion that M. gypseum (Arthrodema gypseum) and M.fulvum (A. fulvum) achieved a similar frequency of isolation in both zones and that the former is a potentially opportunistic pathogen for man and animal.

Digestive enzymes in juvenile green abalone, Haliotis fulgens, fed natural food.

Enzymes responsible for the digestion of food protein by juvenile green abalone (Haliotis fulgens) were studied when fed algae or a sea grass (Phyllospadix torreyi) naturally occurring in the habitat. The effect of food on the composition and activity of the enzymes was also evaluated. Acid, serine proteinases and aminopeptidases, as confirmed by pH profile of activity, specific inhibition and synthetic substrate hydrolysis were found in the digestive organs of juvenile green abalone. Algae and sea grass differentially affected the digestive system in abalone.

Análisis microbiológico en yogurt con probióticos / Microbiological analysis in yogourt with probiótics

Se estudió la calidad microbiológica de 11 muestras de un producto lácteo comercial (yogurt con probióticos), desde supermercados y otros locales afines. Se investigó la presencia de Salmonella spp., Escherichia coli y hongos levaduriformes y filamentosos, mediante la metodología estandarizada recomendada en la literatura y servicios de salud pública. El recuento de lactobacilos presentes se efectuó mediante técnicas de dilución en placa con agar MRS de doble capa y la identificación de lactobacilos presente en el producto aplicando el API-50CHL. Los resultados permitieron establecer que el producto se encuentra libre de contaminación de Salmonella spp., E. coli y hongos, sin embargo, el número de Lactobacillus casei var.rhamnosus viables, fue menor que el indicado en la literatura para obtener efectos benéficos en la salud.

Distribución altitudinal de hongos queratinofilos, epifitos y endófitos en suelos desérticos del norte chileno (II Región, 23°L. S y 68°L. W) / Altitudinal distribution of keratinophilic, epiphytic and endophytic fungi from desertic soils in northern Chile (II Region, 23°L. S y 68°L. W)

En una zona desértica del norte chileno entre los 2200 y 4500m de altura y en 2 períodos estacionales, se determinó la presencia y composición de las comunidades de microhongos queratinofílicos, epifítos y endófitos mediante el empleo de un anzuelo queratínico y vegetal. Las metodologías empleadas permitieron apreciar ciertos aspectos ecológicos de un grupo de hongos tolerantes al estrés y la persistencia en el tiempo de algunas de sus poblaciones en 3 gradientes altitudinales. En 79 muestras de suelo y 67 de vegetales se obtuvieron 1111 aislamientos, repartidos en 78 géneros y 172 especies y los integrantes de los 18 géneros más frecuentes en ambos sustratos y en todas las altitudes reunieron el 80 porciento del total de presencia fúngica. Los Zygomycetes fueron representados por 4 géneros, los Ascomycetes por 11, los Coelomycetes por 8 y los Hyphomycetes por 70. En este último grupo los principales taxa en orden decreciente fueron: Ulocladium, Penicillium, Aspergillus, Acremonium, Alternaria, Cladosporium, Fusarium, Paecilomyces, Trichoderma, Bipolaris, Rhizopus, Aphanocladium y Verticillium. Los integrantes del género Ulocladium Aspergillus, Penicillium y Alternaria obtuvieron las mayores frecuencias en el primer escalón altitudinal en las 3 metodologías, mientras en el escalón más alto fue Penicillium, Ulocladium, Cladosporium y Acremonium. Ocho especies mantuvieron una alta presencia en la mayoría de los sustratos y altitudes. Ulocladium atrum, U. chartarum, Alternaria alternata, Emericella nidulans, Cladosporium cladosporioides, U. botrytis, Aspergillus fumigatus y A. niger, junto a una proporción mayoritaria de especies esporádicas o de baja frecuencia ("ruderal"). La mayoría de los Onygenales y anamorfos relacionados, se aislaron principalmente en verano entre los 2200 y los 4000m. Los más frecuentes fueron: Auxarthron umbrinum, Chrysosporium tropicum, Malbranchea gypsea y Geomyces pannorum. La presencia más alta del grupo (17,4 porciento) en todos los escalones y la persistencia a través del tiempo correspondió a G. pannorum...

Digestive proteinases of Artemesia longinaris (Decapoda, Penaeidae) and relationship with molting.

Digestive proteinase activities of Artemesia longinaris were assayed at different stages of the molting cycle. Total proteolytic activity in the hepatopancreas was highest during postmolt. Trypsin and chymotrypsin activities were highest during intermolt. Specific inhibitors and zymograms of A. longinaris hepatopancreas extracts showed four trypsins (14.79, 15.49, 16.60, 17.38 kDa, respectively) and three chymotrypsins (21.38, 22.91, 27.54 kDa, respectively). Our results suggest that proteolytic activity in the hepatopancreas of A. longinaris is influenced by the molting cycle. Types and activity of prawn digestive enzymes constitute background information to further study the digestive abilities of these organisms and will lead to understanding their nutritional needs and feeding ecology.

Digestive proteinases of red shrimp Pleoticus muelleri (Decapoda, Penaeoidea): partial characterization and relationship with molting.

The present study describes the activity and some characteristics of proteinases in the hepatopancreas of red shrimp Pleoticus muelleri during the different stages of the molting cycle. Proteolytic activity was highest between pH 7.5 and 8. The hepatopancreatic protein content in the premolt stage was higher than in the other stages of the molting cycle (P<0.05). No significant differences were found in total proteolytic activity in the hepatopancreas when comparing molting stages. The proteolytic activity of the P. muelleri hepatopancreas enzyme preparations is the main responsibility of serine proteinases. TLCK, a trypsin inhibitor, reduced azocasein hydrolysis between 26% (intermolt) and 37% (premolt). TPCK, a chymotrypsin inhibitor, did not decrease hydrolytic activity, except for in postmolt. Low trypsin and chymotrypsin activities were found during intermolt, and increased in postmolt. The electrophoretogram of the enzyme extracts shows 12 bands of activity during intermolt (from 16.6 to 53.1 kDa). Some fractions were not detected in the postmolt and premolt stages. Three low molecular weight trypsin forms (17.4, 19.1 and 20 kDa) were found in all molting stages. One band of chymotrypsin (21.9 kDa) was observed in all molting stages. High molecular mass active bands (66-205 kDa) could not be characterized with inhibitors. Comparison of the protease-specific activity of the hepatopancreas of some species indicated a relationship between digestive enzyme activity and feeding habits of the shrimp. Omnivorous shrimp, such as Penaeus vannamei (syn: Litopenaeus vannamei) and Penaeus monodon, showed higher protease activity than the carnivorous shrimp, Penaeus californiensis (syn: Farfantepenaeus californiensis) and P. muelleri. In fact, the enzymatic activity in the hepatopancreas of P. muelleri showed variations in relation to feeding habit and molting cycle.

Trypsin-like enzymes from two morphotypes of the 'living fossil' Triops (Crustacea: Branchiopoda: Notostraca).

Trypsin-like enzymes from two morphotypes (here called short and long) of the 'living fossil' Triops of Baja California Sur, Mexico were studied. Adults of both morphotypes were obtained from outdoor static cultures using dry soil from the natural habitats as a source of cysts and culture substrate. Individual and pooled extracts were made from dissected digestive tubes. The effect of pH and temperature on the trypsin activity was studied using N-alpha-benzoyl-DL-Arg-p-nitroanilide (BAPNA) as substrate. The highest proteolytic activity was found at the same pH with extracts of both morphotypes. At this pH, there was greater proteolytic activity at a lower temperature with the short morphotype extract than with the long morphotype extract. Substrate-SDS-PAGE zymograms showed bands of activity. Short morphotype extracts produced six bands; five of them were serine proteases of which three were trypsin-like enzymes. Long morphotype extracts revealed eight bands; six of them were serine proteases of which three were trypsin-like enzymes.

[Lipoxygenase and trypsin inhibitor inactivation in soymilk processing by direct milling and ultra high temperature (DM-UHT)]. / Inactivación de lipoxigenasas e inhibidores de tripsina en un proceso de obtención de leche de soja por molienda directa y ultra alta temperatura (MD-UAT).

Soymilk production by a new process based on Direct Milling of soy grits and Ultra High Temperature (DM-UHT) has been studied at laboratory scale in order to evaluate solids and protein extraction, lipoxygenases (LO) and Trypsin Inhibitors (TI) inactivation during milling and heat-treatment steps. For TI measurements in soy extracts and soymilk a modification of the classical Kakade method (17) was used. Highest extraction yields were accomplished at 70 degrees C and 2 minutes milling of soy grits. LO was appreciably inactivated when using, as dispersing medium for milling, 0.01M sodium carbonate (Residual Activity 14%) instead of water (Residual Activity 46%), so in this way lower levels of undesired substances can be generated. LO destruction in the resulting suspension was finished by a short heating (30 seconds) from 70 degrees C to boiling temperature (96 degrees C). On the other hand, TI were not fully inactivated in milling nor even in the steaming step at 96 degrees C for many minutes. The TI were inactivated to the accepted levels for soymilk in the final UHT step at 135 degrees C and 2 minutes, being possible at the same time to carry out the simultaneous microorganisms destruction.

Nannizzia racemosa, Chrysosporium lobatum, Penicillium dendriticum y Hyalodendron lignicola: cuatro aislamientos de interes en suelos chilenos / Nannizzia racemosa, Chrysosporium lobatum, Penicillium dendriticum and Hyalodendron lignicola: 4 interesting isolations from chileam soils

Se informa y describen los hallazgos de cuatro especies fúngicas: Nannizzia racemosa, Peniccilium dendriticum y Hyalodendron lignicola aisladas desde el suelo y Chrysosporium lobatum desde el pelaje de un perro

Yeast communities in sandy soils (a beach of V region, Chile) II

Con la finalidad de detectar la sobrevivencia de hongos levaduriformes patógenos o potencialmente patógenos en las arenas de playas recreacionales marinas, información de interés ecológico y relacionada a salud pública, pesquizamos la existencia de levaduras en la zona intertidal y seca en una playa de Viña del Mar (Caleta Abarca), mediante un muestreo mensual entre los meses de Enero a Diciembre de 1982. Por técnicas como el recuento estandarizado en placas y el número indicador de Cooke, detectamos 70 especies levaduriformes distribuidas en 13 géneros: Candida, Cryptococcus, Torulopsis, Brettanomyces, Trichosporon, Rhodotorula, Sporobolomyces, Hansenula, Pichia, Saccaromyces, Debaryomyces, Dekkera, Rhodosporidium. La mayor parte de las especies aisladas son cosmopolitas en su distribución, aislandose básicamente una microbiota residente y transitoria asociada a hospederos que difiere en cantidad y calidad; 22 especies fueron aisladas en zona seca y 18 en la intertidal. Por lo tanto las playas representan un reservorio de levaduras potencialmente patógenas de interés en salud pública. Nuestros resultados sugieren la utilización de las especies del género Candida como uno de los indicadores de contaminación fecal en playas recreacionales