Aislamiento y producción de basidiomas de cepas nativas de Volvariella bombycina (Schaeff) Singer, utilizando desechos agrícolas / Isolation and production of basidiomes from native strains of Volvariella bombycina (Schaeff) Singer, using agro-industrial wastes

Volvariella bombycina es una especie de hongo saprófito comestible que crece en troncos de árboles muertos y sobre la cual existe abundante información acerca de su sabor y propiedades nutricionales y medicinales. En Guatemala esta especie se consume en diversas regiones templado-cálidas del país, pero a la fecha no existe ningún estudio sobre su cultivo a nivel local. La presente investigación se realizó con el fin de conocer el comportamiento de tres cepas guatemaltecas de V. bombycina cultivadas en desechos agroindustriales. Las cepas fueron aisladas de basidiomas recolectados en bosques cercanos a la Ciudad de Guatemala, utilizándose medio PDA para el aislamiento y temperatura de 30 ºC para incubación. En la producción de inóculo se calculó la tasa de extensión radial (RER) sobre granos de sorgo y trigo en cajas de Petri. Para la obtención de basidiomas se evaluaron seis sustratos de desechos agrícolas: pasto jaraguá, caña y olote de maíz, rastrojo de frijol, paja de trigo, paja de arroz y tronco de tonché (Ipomoea murucoides), en frascos de vidrio. Se encontró que no hubo diferencia estadística significativa en el análisis de la RER entre las cepas VNPNU-01 y AADM-01 (p > .05), pero sí con la cepa VNPNU-02 (p < .05). Se obtuvieron basidiomas de V. bombycina en los seis sustratos evaluados, siendo la cepa AADM-01 la más productiva. De acuerdo con este estudio, las tres cepas guatemaltecas de V. bombycina pueden ser utilizadas en la producción de basidiomas en desechos agrícolas, lo que permitiría obtener un alimento nutritivo y generar ingresos a quienes deseen cultivar este hongo.

Volvariella bombycina is a species of edible saprophyte fungus that grows on logs of dead trees and about which there is information about its taste and nutritional and medicinal properties. In Guatemala this species is consumed in several warm regions of the country, but there is still no study on its cultivation locally. The present investigation was carried out in order to know the behavior of three Guatemalan strains of V. bombycina when cultivated in agricultural wastes. The strains were isolated from basidiomata collected in forests close to Guatemala City, using PDA medium and a temperature of 30ºC for incubation. In the inoculum production, the radial extension rate (RER) was calculated using sorghum and wheat grains in Petri dishes. For obtaining basidiomata, six agricultural wastes substrates were analyzed: grazing grass, cane and corn cob, stubble of bean, wheat straw, rice straw and tonché trunk (Ipomoea murucoides), in glass jars. There was found no significant difference in the statistical analysis of the RER with the VNPNU-01 and AADM-01 strains (p > .05), but it was significant with the VNPNU-02 strain (p > .05). Basidiomata of V. bombycina were obtained in the six substrates evaluated, being the AADM-01 strain the most productive. According to this evaluation, the three Guatemalan strains of V. bombycina can be used in the production of basidiomas using agricultural wastes, what would allow the production of a nutritious food and generate another income for those who want to grow this mushroom.

The improvement of competitive saprophytic capabilities of Trichoderma species through the use of chemical mutagens

Abstract The antagonistic potential of Trichoderma strains was assayed by studying the effect of their culture filtrate on the radial growth of Sclerotium rolfsii, the causal agent of chickpea collar rot. Trichoderma harzianum-1432 (42.2%) and Trichoderma atroviride (40.3%) were found to be strong antagonists. To enhance their antagonistic potential, mutagenesis of these two selected strains was performed. Two mutants, Th-m1 and T. atroviride m1, were found to be more effective than their parent strains. The enzymatic activities of the selected parent and mutant strains were assayed, and although both mutants were found to have enhanced enzymatic activities compared to their respective parent strains, Th-m1 possessed the maximum cellulase (5.69 U/mL) and β-1,3-glucanase activity (61.9 U/mL). Th-m1 also showed high competitive saprophytic ability (CSA) among all of the selected parent and mutant strains, and during field experiments, Th-m1 was found to successfully possess enhanced disease control (82.9%).

Efficacy of fungal decolorization of a mixture of dyes belonging to different classes

Dyes are the most difficult constituents to remove by conventional biological wastewater treatment. Colored wastewater is mainly eliminated by physical and chemical procedures, which are very expensive and have drawbacks. Therefore, the advantage of using biological processes, such as the biotransformation of dyes, is that they may lead to complete mineralization or formation of less toxic products. To prove the possibility of using fungal processes for decolorization and other applications, the analysis of the toxicity of the processes' products is required. The decolorization of the mixture of two dyes from different classes - triphenylmethane brilliant green and azo Evans blue (GB - total concentration 0.08 g/L, proportion 1:1 w/w) - by Pleurotus ostreatus (BWPH and MB), Gloeophyllum odoratum (DCa), RWP17 (Polyporus picipes) and Fusarium oxysporum (G1) was studied. Zootoxicity (Daphnia magna) and phytotoxicity (Lemna minor) changes were estimated at the end of the experiment. The mixture of dyes was significantly removed by all the strains that were tested with 96 h of experimental time. However, differences among strains from the same species (P. ostreatus) were noted. Shaking improved the efficacy and rate of the dye removal. In static samples, the removal of the mixture reached more than 51.9% and in shaken samples, more than 79.2%. Tests using the dead biomass of the fungi only adsorbed up to 37% of the dye mixture (strain BWPH), which suggests that the process with the living biomass involves the biotransformation of the dyes. The best results were reached for the MB strain, which removed 90% of the tested mixture under shaking conditions. Regardless of the efficacy of the dye removal, toxicity decreased from class V to class III in tests with D. magna. Tests with L. minor control samples were classified as class IV, and samples with certain strains were non-toxic. The highest phytotoxicity decrease was noted in shaken samples where the elimination of dye mixture was the best.

Eucalyptus grandis Hill ex Maiden inoculated with Pisolithus microcarpus (UFSC-Pt116) in land subject to the sandy process in southern Brazil

Eucalypts is one of the main species used for commercial reforestation in the state of Rio Grande do Sul, Brazil. This study aimed to evaluate the survival and early growth of eucalyptus trees in an area subject to sandy process after three years of growth. The Eucalyptus grandis seedlings were grown in a greenhouse, innoculated or not with the isolated ectomycorrhizal Pisolithus microcarpus (UFSC-Pt116), produced in peat or Entisol. After 120 days, the seedlings were transplanted to an area subject to the sandy process, in the city of São Francisco de Assis, RS. The plants have been evaluated regarding survival, height, stem diameter, nitrogen, phosphorus and potassium levels and total phosphorus, inorganic phosphorus, organic phosphorus and wood production on different days after planting. The seedlings grown on the Entisol which was inoculated with the isolated UFSC-Pt116 presented higher survival rates, height, stem diameter, nitrogen concentration and wood production compared to the non-inoculated seedlings. Inoculation with ectomycorrhizal fungi enhanced the production of E. grandis seedlings in survival rates, height, stem diameter.

Concentration, characterization and application of lipases from Sporidiobolus pararoseus strain

Lipases produced by a newly isolated Sporidiobolus pararoseus strain have potential catalytic ability for esterification reactions. After production, the enzymatic extracts (conventional crude and precipitated, 'CC' and 'CP', and industrial crude and precipitated, 'IC' e 'IP') were partially characterized. The enzymes presented, in general, higher specificity for short chain alcohols and fatty acids. The precipitated extract showed a good thermal stability, higher than that for crude enzymatic extracts. The 'CC' and 'CP' enzymes presented high activities after exposure to pH 6.5 and 40 ºC. On the other hand, the 'IC' and 'IP' extracts kept their activities in a wide range of pH memory but presented preference for higher reaction temperatures. Preliminary studies of application of the crude lipase extract in the enzymatic production of geranyl propionate using geraniol and propionic acid as substrates in solvent-free system led to a reaction conversion of 42 ± 1.5%.

Halotolerance, ligninase production and herbicide degradation ability of basidiomycetes strains

Fungi have been recently recognized as organisms able to grow in presence of high salt concentration with halophilic and halotolerance properties and their ligninolytic enzyme complex have an unspecific action enabling their use to degradation of a number of xenobiotic compounds. In this work, both the effect of salt and polyols on growth of the basidiomycetes strains, on their ability to produce ligninolytic enzyme and diuron degradation were evaluated. Results showed that the presence of NaCl in the culture medium affected fungal specimens in different ways. Seven out of ten tested strains had growth inhibited by salt while Dacryopinax elegans SXS323, Polyporus sp MCA128 and Datronia stereoides MCA167 fungi exhibited higher biomass production in medium containing 0.5 and 0.6 mol.L-1 of NaCl, suggesting to be halotolerant. Polyols such as glycerol and mannitol added into the culture media improved the biomass and ligninases production by D. elegans but the fungus did not reveal consumption of these polyols from media. This fungus degraded diuron in medium control, in presence of NaCl as well as polyols, produced MnP, LiP and laccase.

Grape stalks as substrate for white rot fungi, lignocellulolytic enzyme production and dye decolorization / Uso del escobajo como sustrato para el crecimiento de hongos de la pudrición blanca, la producción de enzimas ligninolíticas y la decoloración de tinturas

The aim of this work was to evaluate the potential of grape stalks, an agroindustrial waste, for growth and lignocellulolytic enzyme production via solid-state fermentation, using the following three white rot fungi: Trametes trogii, Stereum hirsutum and Coriolus antarcticus. The decolorization of several dyes by the above mentioned cultures was also investigated. Similar values of dry weight loss of the substrate were measured after 60 days (33-43 %). C. antarcticus produced the highest laccase and Mn-peroxldase activities (33.0 and 1.6 U/g dry solid). The maximum endoglucanase production was measured in S. hirsutum cultures (10.4 U/g), while the endoxylanase peak corresponded to T. trogii (14.6 U/g). The C. antarcticus/grape stalk system seems potentially competitive in bioremediation of textile processing effluents, attaining percentages of decolorization of 93, 86, 82, 82, 77, and 58 % for indigo carmine, malachite green, azure B, remazol brilliant blue R, crystal violet and xylidine, respectively, in 5 h.

El objetivo de este trabajo fue evaluar el potencial del escobajo, un residuo agroindustrial, como sustrato para el crecimiento y la producción de enzimas lignocelulósicas de tres hongos causantes de pudrición blanca en la madera: Trametes trogii, Stereum hirsutum y Coriolus antarcticus. Para ello se utilizaron técnicas de fermentación en estado sólido. También se ensayó la decoloración de colorantes industriales sobre estos cultivos. La pérdida de peso seco del sustrato fue similar después del día 60 (33-43 %). C. antarcticus produjo las mayores actividades de lacasa y Mn-peroxidasa (33,0 y 1,6 U/g peso seco). La mayor actividad endoglucanasa fue medida en cultivos de S. hirsutum (10,4 U/g), y la mayor actividad endoxilanasa en T. trogii (14,6 U/g). El sistema C. antarcticus/escobap mostró un importante potencial para su aplicación en la biorremediación de efluentes textiles, con porcentajes de decoloración de 93, 86, 82, 82, 77 y 58 % para índigo carmín, verde de malaquita, azure B, azul R brillante de remazol, cristal violeta y xilidina, respectivamente, en 5 h.

Xanthophyllomyces dendrorhous (Phaffia rhodozyma) on stromata of Cyttaria hariotii in northwestern Patagonian Nothofagus forests

The occurrence and distribution of Xanthophyllomyces dendrorhous associated with Cyttaria hariotii parasitizing three Nothofagus species (N. dombeyi, N. antarctica and N. pumilio) in northwestern Patagonia (Argentina), as well as the factors that may affect this distribution were herein studied. Between 2000 and 2007, samples were obtained from 18 different locations. Based on physiological tests and morphological characteristics of sexual structures, 72 isolates were identified as X. dendrorhous. Representative strains were studied by MSP-PCR fingerprinting and sequence analysis of the ITS region. MSP-PCR fingerprints were similar for the newly isolated strains, and were also identical to the profiles of the strains previously found in this region. Patagonian strains appear to be a genetically uniform and distinct population, supporting the hypothesis that the association with different host species has determined genetically distinct X. dendrorhous populations worldwide. X. dendrorhous was recovered from N. dombeyi and N. antarctica. Approximately half the sampling sites and samples were positive for X. dendrorhous, but the isolation recovery rate was low. X. dendrorhous was absent in the early stages of ascostromata maturation, becoming more abundant in later stages. The present work represents a step forward in the understanding of the natural distribution and ecology of this biotechnologically relevant yeast.

Xanthophyllomyces dendrorhous (Phaffia rhodozyma) asociado a estromas de Cyttaria hariotii en bosques de Nothofagus en el noroeste de la Patagonia. Se estudió la ocurrencia y la distribución de Xanthophyllomyces dendrorhous asociado a Cyttaria hariotii en tres especies de Nothofagus (N. dombeyi, N. antarctica y N. pumilio) del noroeste de la Patagonia (Argentina), y los factores que podrían afectar esta distribución. El muestreo se realizó entre 2000 y 2007 en 18 sitios diferentes. Según las pruebas fisiológicas y las características morfológicas de las estructuras sexuales, 72 de los aislamientos obtenidos se identificaron como X. dendrorhous. Se estudiaron cepas representativas mediante la técnica de MSP-PCR fingerprinting y secuenciación de la región ITS. Los perfiles de MSP-PCR fueron similares, tanto entre los nuevos aislamientos como entre estos y los de cepas previamente obtenidas en la región. Aparentemente, las cepas patagónicas forman una población genéticamente uniforme y distinta de otras poblaciones. Esto apoya la hipótesis de que la asociación con diferentes especies hospedadoras ha determinado la diferenciación genética de X. dendrorhous en todo el mundo. X. dendrorhous se recuperó de N. dombeyi y de N. antarctica. Aproximadamente la mitad de los sitios de muestreo y de muestras fueron positivos para X. dendrorhous, pero la tasa de aislamiento fue muy baja. X. dendrorhous está ausente en estadios tempranos de maduración de ascostromas y se hace más abundante en estadios más tardíos. El presente trabajo contribuye al mejor entendimiento de la distribución natural y la ecología de esta levadura, de relevancia biotecnológica.

Criopreservação do gênero Pleurotus a -20 °c e a -70 °c / Criopreservación del género Pleurotus a -20 ºc y -70 ºc / Criopreservation of genus Pleurotus at -20 °c and -70 °c

O desenvolvimento de técnicas de criopreservação utilizando temperaturas comerciais (-20 °C) na conservação de Basidiomicetos é uma vantagem técnica e econômica para a produção de biomassa e/ou biocompostos, porém geralmente associada a problemas de danos celulares. O objetivo deste trabalho foi avaliar o uso de substratos para o crescimento do fungo associado a agentes crioprotetores na criopreservação a -20 ºC e a -70 ºC do gênero Pleurotus. O fungo, crescido em ágar-batata-dextrose ou em grãos de aveia, foi criopreservado a -20 °C e a -70 °C na presença dos crioprotetores glicerol, dimetilsulfóxido, glicose, sacarose, extrato de malte e polietilenoglicol. Foram discutidas as vantagens do substrato em associação com o crioprotetor, nas diversas temperaturas de crioproteção. Concluiu-se que o substrato utilizado para o crescimento do micélio influencia na viabilidade de recuperação do fungo criopreservado, em ambas as temperaturas, sendo que grãos de aveia promovem melhor recuperação do fungo e melhor vigor micelial. Os resultados sugerem uma simplificação técnica e redução de custos de manutenção de linhagens de Basidiomicetos.

The development of cryopreservation techniques using commercial temperatures (-20 °C) to preserve Basidiomycetes is an economical advantage for biomass and/or biocompound production; however, it is usually associated to cellular damages. The objective of this work was to evaluate the use of substrates for the fungus growth associated to cryoprotectants for the cryopreservation of Genus Pleurotus at -20ºC and -70ºC. The fungus, grown in either potato dextrose agar or oat grains, was cryopreserved at -20 °C or -70 °C with glycerol, dimethyl sulfoxide, glucose, sucrose, malt extract and polyethyleneglycol. The advantages of the substrate associated with the cryoprotectant at different cryopreservation temperatures were discussed. It was concluded that the substrate used for the mycelial growth positively influences the viability of the recovery of the cryopreserved fungus on both temperatures – oat grains promote better recovery and mycelial vigor. Those results suggest technical simplification and reduction of maintenance costs of culture collections of Basidiomycetes.

El desarrollo de técnicas de criopreservación utilizando temperaturas comerciales (-20ºC) en la conservación de Basidiomicetos es una ventaja técnica y económica para la producción de biomasa y/o biocompuestos, pero generalmente está asociada a problemas de daños celulares. El objetivo de esta investigación fue evaluar el uso de substratos para el crecimiento del hongo, asociado a agentes crioprotectores en la criopreservación a -20ºC y a -70ºC del género PleurotUs. Elhongo, crecido en agar-patata-dextrosa o en granos de avena, fue criopreservado a -20ºC y a -70ºC en la presencia de los crioprotectores glicerol, dimetilsulfóxido, glucosa, sacarosa, extracto de malte y polietilenoglicol. Fueron discutidas las ventajas del substrato en asociación con el crioprotector, en las diversas temperaturas de crioprotección. Se concluyó que el substrato utilizado para el crecimiento del micelio influencia en la viabilidad de recuperación del hongo criopreservado, en ambas las temperaturas, siendo que granos de avena promueven mejor recuperación del hongo y mejor vigor del micelio. Los resultados sugieren una simplificación técnica y reducción de costos de manutención de liñajes de Basidiomicetos.

Notas sobre el género Geastrum pers. en Chile central / Notes on the genus Geastrum Pers. in Central Chile

Se reporta el hallazgo de Geastrum campestre, G. fornicatum y G. pectinatum en la zona central de Chile. Junto a la descripción e ilustraciones de estas especies, se comentan aspectos de su ecología, taxonomía y distribución. G. campestre es nuevo para el catálogo micológico chileno.

Geastrum campestre, G. fornicatum, and G. pectinatum are reported from Central Chile. Descriptions and illustrations of these species are provided with comments on their ecology, taxonomy and distribution. G. campestre is new to Chile.

Lignolytic enzymes produced by Trametes villosa ccb176 under different culture conditions

The expression of the enzymatic system produced by basidiomycetous fungi, which is involved in the degradation of xenobiotics, mainly depends on culture conditions, especially of the culture medium composition. Trametes villosa is a strain with a proven biotechnological potential for the degradation of organochlorine compounds and for the decolorization of textile dyes. The influence of glucose concentration, addition of a vegetable oil-surfactant emulsion, nature of the surfactant and the presence of manganese and copper on the growth, pH and production of laccase, total peroxidase and manganese-dependent peroxidase activities were evaluated. In general, acidification of the medium was observed, with the pH reaching a value close to 3.5 within the first days of growth. Laccase was the main activity detected under the different conditions and was produced throughout the culture period of the fungus, irrespective of the growth phase. Supplementation of the medium with vegetable oil emulsified with a surfactant induced manganese-dependent peroxidase activity in T. villosa. Higher specific yields of laccase activity were obtained with the addition of copper.

A expressão do sistema enzimático produzido por fungos basidiomicetos envolvido na degradação de xenobióticos é bastante dependente das condições de cultivo, principalmente da composição do meio de cultivo. Trametes villosa CCB176 é uma linhagem com comprovado potencial biotecnológico para degradação de compostos organoclorados e descoloração de corantes têxteis. Foi avaliada a influência da concentração de glicose, adição de emulsão de óleo vegetal e surfactante, natureza do surfactante e os metais manganês e cobre no crescimento, pH e na produção das atividades de lacase, de peroxidases totais e de peroxidase dependente de manganês. No geral, ocorreu acidificação do meio com pH atingindo valor próximo a 3,5, nos primeiros dias de crescimento. Lacase foi a principal atividade detectada nas diferentes condições e sua produção se deu durante todo o período de cultivo do fungo, independente da fase de crescimento. Suplementação do meio com óleo vegetal emulsificado com surfactante resultou em indução da atividade de peroxidase dependente de manganês produzida por T. villosa. Maiores valores de rendimento específico da atividade de lacase foram propiciados pelo cobre.

Battarrea stevenii (Liboschitz) Fr. en Paposo II Región de Chile / (Battarrea stevenii (Liboschitz) Fr. in Paposo second Region of Chile

Se reporta el hallazgo de Battarrea stevenii (Liboschitz) Fr., un raro basidiomiceto xerofítico, en la localidad de Paposo, II Región de Chile. Junto a la descripción e ilustración del material examinado, se entregan comentarios sobre su ecología, taxonomía y distribución.

Battarrea stevenii (Liboschitz) Fr., a rare xerophytic basidiomycete is reported from Paposo, Second Region of Chile. Besides description and illustration of the examined samples, comments about its ecology, taxonomy and distribution are also discussed.

Enhanced proteolysis leads to pre-mature cell death under the influence of elicitor like mycelial components from karnal bunt (tilletia indica) pathogen in wheat callus cultures.

Calli raised from mature embryos of susceptible wheat cultivar WH 542 were used in the present study as in vitro bioassay system to study the influence of disease determinant(s) of Karnal bunt (Tilletia indica), a semi-biotrophic fungal pathogen of wheat. Influence of elicitor and conditioned medium (CM) prepared from fungal cultures of T. indica was investigated on induction of programmed cell death (PCD). Induction of PCD was observed as hypersensitive response (HR) in terms of browning at localized regions of callus cultures and induction of proteolytic enzyme(s). Elicitor treated calli showed higher induction of protease activity than untreated and CM-treated cultures, which showed not much change in the activity. It was further substantiated by gel protease assay and activation of caspase-3 like protein(s) in callus cultures that clearly suggested the presence of signaling molecule(s) in the fungal elicitor preparation rather than in conditioned medium. This study further demonstrated that only elicitor preparation possesses such molecule(s), which might be cell wall bound components, rather than secretory in nature as CM was unable to induce PCD in wheat callus cultivars.

Arbuscular mycorrhiza-like biotechnological potential of Piriformospora indica, which promotes the growth of Adhatoda vasica Nees

We report the growth promoting potential of Piriformospora indica, which is a newly discovered arbuscular mycorrhiza-like fungus. It is a facultative symbiont and unlike arbuscular mycorrhizal fungi, it can be cultured in vitro. Adhatoda vasica is a medicinal plant. Rapid proliferation of roots was recorded in A. vasica withan important root colonization estimated to 95 percent after 6 months. P. indica improved growth of A. vasica. This association forms a new host-symbiont combination.

Isolation and identification of marine chitinolytic bacteria and their potential in antifungal biocontrol.

Chitinolytic marine bacterial strains (30) were isolated from the sea dumps at Bhavnagar, India. They were screened as chitinase producers on the basis of zone of clearance on chitin agar plates incorporated with calcofluor white M2R for the better resolution. Out of these, three strains namely, Pseudomonas sp., Pantoea dispersa and Enterobacter amnigenus showed high chitinase production. They were also found to produce proteases and therefore have a good potential for use as antifungal biocontrol agents for the control of fungal plant pathogens. These strains could degrade and utilize the mycelia of Macrophomina phaseoliena (Tassi) Goidanich and Fusarium sp. In vitro, these strains could inhibit the growth of Fusarium sp. and M. phaseolina. The culture filtrate inhibiting hyphal elongation was observed microscopically.

Modulation of antigenicity of mycelial antigens during developmental cycle of Karnal bunt (Tilletia indica) of wheat.

Indirect enzyme linked immunosorbent assays (ELISA) were developed using polyclonal antibodies against soluble cytoplasmic (SCA) and insoluble cell wall antigens (ICWA) for monitoring modulation of mycelial antigens during growth cycle of T. indica. With SCA, continuous decrease in ELISA reactivity was observed in maturing fungus cultures, suggesting that SCA were expressed predominantly during early vegetative phase and their decreasing role was apparent as the fungus matures possibly towards sporogenous mycelium. In case of ICWA, the reaction profile showed an increase up to exponential phase of growth probably due to increase in the cell division and branching of mycelium. But later, ICWA antibody reactivity was decreased which may be due to conversion of mycelial phase to sporogenous phase, a quiescent stage of growth. Characterization of changes in antigenic configuration during developmental cycle of Tilletia indica by these antibodies could prove to be useful in identification of developmentally related and virulence marker(s).

Fomes pectinatis: an aeroallergen in India.

This work is focused on the aerobiology and allergenicity of Fomes pectinatis in India. The atmospheric concentration of Fomes basidiospores was recorded and the antigens were prepared from spore (FSE) and whole body (FWBE) materials. The intradermal (ID) and prick (PT) skin tests were conducted on 172 patients having respiratory allergy. The period from July to October has been recorded as having a higher concentration of Fomes spores. The maximum counts (67 spores/m3) were observed from the North Delhi site in the month of July, 1989, compared with 550 spores/m3 in the South Delhi site. Marked skin positivity (2+ and above) varied from 9.8% to FSE to 22% to FWBE. Nine out of twelve ID positive patients (2+ to 3+) to FSE also gave PT positive response. For FWBE, similar ID and PT response was obtained in 80% of cases. The soluble protein content of FSE was 0.37 mg/ml, whereas, for FWBE it was 0.70 mg/ml. It was observed through ELISA that almost all patients had significantly raised FP specific IgE levels in their sera. The current study, therefore, indicates that Fomes pectinatis may be a prevalent aeroallergen in India.

Colonization potential of banana leaves for growth of pleurotus species

Um teste de colonizaçäo por Pleurotus sp. Florida, P. ostreatoroseus e P.sajor-caju, fungos comestíveis, foi realizado visando conhecer a potencialidade da palha de folha de bananeira (PB), resíduo lignocelulósico, como substrato para o cultivo desses fungos. Utilizou-se a PB e esta misturada ao bagaço de cana (PBBC) ou sabugo de milho (PBSM). A palha de trigo (PT) foi empregada como parâmetro de comparaçäo por ser o resíduo tradicionalmente empregado. As palhas picadas, em partículas de aproximadamente 0,5 cm de comprimento, foram reumedecidas até alcançar aproximadamente 70 por cento de umidade; em seguida foram esterilizadas, em placas de Petri, a 120ºC por 2 horas. O pH dos substratos

Cultivo de Pleurotus ostreatus y especies afines (Fungi: Pleurotaceae) sobre medios naturales semi-estériles / Cultivation of Pleurotus ostreatus and allied species (Fungi:Pleurotaceae) upon semi-esterile natural media

Pleurotus ostreatus (Jacq. ex Fr.) Quélet and its allies are edible mushrooms whose cultivation is succesful in parts of Europe and Asia. In Costa Rica only Agaricus bisporus has been commercially cultured, but requires elaborate facilities. The use of waste material (e.g. sawdust, rice straw, sugar cane debris) and mon-controlled environmental conditions suitable for easy artisanal cultivation of Pleirotus ostreatus is reported here.