[Degradation of plant waste by Coprinus truncorum using 2 culture methods]. / Degradación de residuos vegetales por Coprinus truncorum usando dos métodos de cultivo.

Degradation of yard wastes by Coprinus truncorum growing in a vertical aereated bioreactor or in flasks was studied. There was a constant decay of reducing sugars in the medium that avoided their accumulation and their possible repression of degradative enzymes. Endoxylanase activity at first showed a similar pattern in both culture conditions, with maximal activity on the 12th day, but flasks maintained a high activity thereafter. Flasks also showed a higher endoglucanase activity with a peak on the 18th day, whereas the maximal value in the bioreactor was reached on the 26th day. No Mn-peroxidase and only low values of laccase activity were found. The measurements of pH and soluble proteins during the incubation period were suitable indicators of the degradation process by C. truncorum.

Degradación de residuos vegetales por Coprinus truncorum usando dos métodos de cultivo / Degradation of plant waste by Coprinus truncorum using 2 culture methods

Degradation of yard wastes by Coprinus truncorum growing in a vertical aereated bioreactor or in flasks was studied. There was a constant decay of reducing sugars in the medium that avoided their accumulation and their possible repression of degradative enzymes. Endoxylanase activity at first showed a similar pattern in both culture conditions, with maximal activity on the 12th day, but flasks maintained a high activity thereafter. Flasks also showed a higher endoglucanase activity with a peak on the 18th day, whereas the maximal value in the bioreactor was reached on the 26th day. No Mn-peroxidase and only low values of laccase activity were found. The measurements of pH and soluble proteins during the incubation period were suitable indicators of the degradation process by C. truncorum.

Degradación de residuos vegetales por Coprinus truncorum usando dos métodos de cultivo / Degradation of plant waste by Coprinus truncorum using 2 culture methods

Degradation of yard wastes by Coprinus truncorum growing in a vertical aereated bioreactor or in flasks was studied. There was a constant decay of reducing sugars in the medium that avoided their accumulation and their possible repression of degradative enzymes. Endoxylanase activity at first showed a similar pattern in both culture conditions, with maximal activity on the 12th day, but flasks maintained a high activity thereafter. Flasks also showed a higher endoglucanase activity with a peak on the 18th day, whereas the maximal value in the bioreactor was reached on the 26th day. No Mn-peroxidase and only low values of laccase activity were found. The measurements of pH and soluble proteins during the incubation period were suitable indicators of the degradation process by C. truncorum.(AU)

Degradación de residuos vegetales por Coprinus truncorum usando dos métodos de cultivo. / [Degradation of plant waste by Coprinus truncorum using 2 culture methods]

Degradation of yard wastes by Coprinus truncorum growing in a vertical aereated bioreactor or in flasks was studied. There was a constant decay of reducing sugars in the medium that avoided their accumulation and their possible repression of degradative enzymes. Endoxylanase activity at first showed a similar pattern in both culture conditions, with maximal activity on the 12th day, but flasks maintained a high activity thereafter. Flasks also showed a higher endoglucanase activity with a peak on the 18th day, whereas the maximal value in the bioreactor was reached on the 26th day. No Mn-peroxidase and only low values of laccase activity were found. The measurements of pH and soluble proteins during the incubation period were suitable indicators of the degradation process by C. truncorum.

[Influence of culture conditions on ligninolytic activity of Stereum hirsutum]. / Efecto de las condiciones de cultivo sobre la actividad ligninolítica de Stereum hirsutum.

Stereum hirsutum BAFC 2234 was tested for growth kinetics and ligninolytic enzyme production. The strain showed weak coincidences with widely studied organisms (Phanerochaete chrysosporium, Pleurotus ostreatus) when the response to nitrogen sources was assayed. This could be interpreted as a different regulation to nitrogen metabolism for S. hirsutum BAFC 2234. Alternative carbon sources and the addition of veratryl alcohol and wood extracts were also tested showing partial correspondence with other ligninolytic fungi. On the basis of the high enzymatic activities observed, S. hirsutum BAFC 2234 could be a suitable source of lignin degrading system aiming techological processes.

Efecto de las condiciones de cultivo sobre la actividad ligninolÝtica de Stereum hirsutum / Influence of culture conditions on ligninolytic activity of Stereum hirsutum

Stereum hirsutum BAFC 2234 was tested for growth kinetics and ligninolytic enzyme production. The strain showed weak coincidences with widely studied organisms (Phanerochaete chrysosporium, Pleurotus ostreatus) when the response to nitrogen sources was assayed. This could be interpreted as a different regulation to nitrogen metabolism for S. hirsutum BAFC 2234. Alternative carbon sources and the addition of veratryl alcohol and wood extracts were also tested showing partial correspondence with other ligninolytic fungi. On the basis of the high enzymatic activities observed, S. hirsutum BAFC 2234 could be a suitable source of lignin degrading system aiming techological processes.

Efecto de las condiciones de cultivo sobre la actividad ligninolYtica de Stereum hirsutum / Influence of culture conditions on ligninolytic activity of Stereum hirsutum

Stereum hirsutum BAFC 2234 was tested for growth kinetics and ligninolytic enzyme production. The strain showed weak coincidences with widely studied organisms (Phanerochaete chrysosporium, Pleurotus ostreatus) when the response to nitrogen sources was assayed. This could be interpreted as a different regulation to nitrogen metabolism for S. hirsutum BAFC 2234. Alternative carbon sources and the addition of veratryl alcohol and wood extracts were also tested showing partial correspondence with other ligninolytic fungi. On the basis of the high enzymatic activities observed, S. hirsutum BAFC 2234 could be a suitable source of lignin degrading system aiming techological processes.(AU)

Efecto de las condiciones de cultivo sobre la actividad ligninolítica de Stereum hirsutum. / [Influence of culture conditions on ligninolytic activity of Stereum hirsutum]

Stereum hirsutum BAFC 2234 was tested for growth kinetics and ligninolytic enzyme production. The strain showed weak coincidences with widely studied organisms (Phanerochaete chrysosporium, Pleurotus ostreatus) when the response to nitrogen sources was assayed. This could be interpreted as a different regulation to nitrogen metabolism for S. hirsutum BAFC 2234. Alternative carbon sources and the addition of veratryl alcohol and wood extracts were also tested showing partial correspondence with other ligninolytic fungi. On the basis of the high enzymatic activities observed, S. hirsutum BAFC 2234 could be a suitable source of lignin degrading system aiming techological processes.

[Simple method for determining cellulolytic activity in fungi]. / Método simple para determinar actividad celulolítica en hongos.

Wild fungal strains isolated from litter and soil were inoculated in test tubes containing a synthetic medium with 0.5% sodium carboxymethylcellulose (CMC) as sole carbon source. After the incubation time, cylindrical probes were taken from each tube using a borer and stained with Congo red 0.1% to reveal the remaining CMC. The relative cellulase activity was estimated by measuring the deepness of the clearing zone, and the growth by the limit of mycelial penetration in the medium. The ratio: hydrolysis zone/depth of growth, provides additional information to compare strains. A test using culture supernatants of liquid media growing strains was developed for enzyme assay using a modification of the cylinder-plate method. Petri dishes were filled with agar-CMC medium and cups were cut off with a steel punch. Such cups were filled with culture supernatants. After incubation, the plated were stained with Congo red, and the diameter of each cleared zone was recorded. Comparative studies of strains could be performed as well as quantitation of enzyme activity using a standard cellulase solution and computing the area of the cleared zones. This method may be useful when a large number of strains must be tested for cellulolytic activity or when conventional tests fail for assaying enzymatic induction in vitro.

[Kinetics of xylanase and cellulase production by Ascobolus gamundii (Fungi, Ascomycotina)]. / Cinética de producción de xilanasas y celulasas por Ascobolus gamundii (Fungi, Ascomycotina).

Growth and cellulase-xylanase enzyme systems production by Ascobolus gamundii were evaluated in synthetic media with or without natural inducers. The basal level of enzyme complexes was determined using glucose as carbon source. With crystalline cellulose, the amount of endoglucanase and beta-glucosidase was 2-4 times the basal, and the level of endoxylanase and beta-xylosidase was 3 times higher than that observed with glucose. When using xylan as carbon source, endoxylanase and endoglucanase were induced. The higher production of the enzyme systems was observed during the log-phase growth of A. gamundii with a mixture of cellulose and xylan as carbon source. The generalized induction of both enzyme complexes could be due to evolutive adaptation to the substrate (herbivore dung) in which cellulose and hemicellulose are associated to conform the plants cell-walls.

Evaluación de la capacidad celulolítica de Ascobolus furfuraceus (Fungi, Ascomycotina) / [Evaluation of the cellulolytic capacity of Ascobolus furfuraceus (Fungi, Ascomycotina)]

Growth kinetic variables (dry weight, mycelial protein, extracellular protein and pH evolution) were measured in Ascobolus furfuraceus cultures either with soluble cellulose (CMC) or crystalline cellulose as only carbon sources. When growing on CMC the mycelial protein production reached a maximum at 14 days, while the extracellular protein was maximal at 17 days. On crystalline cellulose more delay was observed (4 and 14 days, respectively). Straight lineal correspondence (r = 0.9883) was observed between the extracellular protein production and enzymatic activity kinetics, showing parallel behavior of these variables. When the biomass and extracellular protein production rates were analysed, the maxima were observed at diverse growth stages. For CMC, the dry weight production rythm precedes the cellulolytic system liberation rythm (maxima at 9 and 14 days, respectively). When crystalline cellulose was the substrate, the maximal rates were inverse, 16th day for biomass production rythm and 12th day for enzyme release rythm. On the basis of such tests and analyses, a model to explain cellulose degration by A. furfuraceus, is proposed.

[Evaluation of the cellulolytic capacity of Ascobolus furfuraceus (Fungi, Ascomycotina)]. / Evaluación de la capacidad celulolítica de Ascobolus furfuraceus (Fungi, Ascomycotina).

Growth kinetic variables (dry weight, mycelial protein, extracellular protein and pH evolution) were measured in Ascobolus furfuraceus cultures either with soluble cellulose (CMC) or crystalline cellulose as only carbon sources. When growing on CMC the mycelial protein production reached a maximum at 14 days, while the extracellular protein was maximal at 17 days. On crystalline cellulose more delay was observed (4 and 14 days, respectively). Straight lineal correspondence (r = 0.9883) was observed between the extracellular protein production and enzymatic activity kinetics, showing parallel behavior of these variables. When the biomass and extracellular protein production rates were analysed, the maxima were observed at diverse growth stages. For CMC, the dry weight production rythm precedes the cellulolytic system liberation rythm (maxima at 9 and 14 days, respectively). When crystalline cellulose was the substrate, the maximal rates were inverse, 16th day for biomass production rythm and 12th day for enzyme release rythm. On the basis of such tests and analyses, a model to explain cellulose degration by A. furfuraceus, is proposed.

Evaluación de la capacidad celulolítica de Ascobolus furfuraceus (Fungi, Ascomycotina). / [Evaluation of the cellulolytic capacity of Ascobolus furfuraceus (Fungi, Ascomycotina)]

Growth kinetic variables (dry weight, mycelial protein, extracellular protein and pH evolution) were measured in Ascobolus furfuraceus cultures either with soluble cellulose (CMC) or crystalline cellulose as only carbon sources. When growing on CMC the mycelial protein production reached a maximum at 14 days, while the extracellular protein was maximal at 17 days. On crystalline cellulose more delay was observed (4 and 14 days, respectively). Straight lineal correspondence (r = 0.9883) was observed between the extracellular protein production and enzymatic activity kinetics, showing parallel behavior of these variables. When the biomass and extracellular protein production rates were analysed, the maxima were observed at diverse growth stages. For CMC, the dry weight production rythm precedes the cellulolytic system liberation rythm (maxima at 9 and 14 days, respectively). When crystalline cellulose was the substrate, the maximal rates were inverse, 16th day for biomass production rythm and 12th day for enzyme release rythm. On the basis of such tests and analyses, a model to explain cellulose degration by A. furfuraceus, is proposed.

[Morphology of the mycelium of Ascobolus furfuraceus using different sources of nitrogen]. / Morfología del micelio de Ascobolus furfuraceus con distintas fuentes de nitrógeno.

Ascobolus furfuraceus mycelium showed morphological variations when grown with different nitrogen sources. The hyphae were compared using as parameters cell diameter and length, branching and vacuolization. The variations in cell size, vacuolar area and branching, in response to the nitrogen source, suggest that the nitrogen régime plays a controlling role in the growth of the mycelium as well as in the morphogenesis of the cells. The results are discussed in relation to previous data on the metabolic efficiency of the fungus.

Morfología del micelio de Ascobolus furfuraceus con distintas fuentes de nitrógeno. / [Morphology of the mycelium of Ascobolus furfuraceus using different sources of nitrogen]

Ascobolus furfuraceus mycelium showed morphological variations when grown with different nitrogen sources. The hyphae were compared using as parameters cell diameter and length, branching and vacuolization. The variations in cell size, vacuolar area and branching, in response to the nitrogen source, suggest that the nitrogen régime plays a controlling role in the growth of the mycelium as well as in the morphogenesis of the cells. The results are discussed in relation to previous data on the metabolic efficiency of the fungus.

[Assays of nutrition in Ascobolus furfuraceus. Sources of nitrogen]. / Ensayos de nutrición en Ascobolus furfuraceus. Fuentes de nitrógeno.

The effect of various nitrogen sources on growth and efficiency parameters of Ascobolus furfuraceus was investigated. As nitrogen sources, sodium nitrate and nitrite, inorganic ammonium salts and nitrated organic compounds have been used. The results showed that all of them could be used by the fungus, with the exceptions of sodium nitrite and ammonium oxalate. Good correlation was observed among the growth parameters, the 'economic coefficients' of uptake and internal conversion of sources, and the specific respiration rates. The best nitrogen source - estimated as growth and efficiency parameters - was ammonium carbonate in the culture conditions used. The possibility of heterotrophic carbon fixation is discussed.

Ensayos de nutrición en Ascobolus furfuraceus. Fuentes de nitrógeno. / [Assays of nutrition in Ascobolus furfuraceus. Sources of nitrogen]

The effect of various nitrogen sources on growth and efficiency parameters of Ascobolus furfuraceus was investigated. As nitrogen sources, sodium nitrate and nitrite, inorganic ammonium salts and nitrated organic compounds have been used. The results showed that all of them could be used by the fungus, with the exceptions of sodium nitrite and ammonium oxalate. Good correlation was observed among the growth parameters, the economic coefficients of uptake and internal conversion of sources, and the specific respiration rates. The best nitrogen source - estimated as growth and efficiency parameters - was ammonium carbonate in the culture conditions used. The possibility of heterotrophic carbon fixation is discussed.

Ensayos de nutrición en Ascobolus furfuraceus. Fuentes de nitrógeno / [Assays of nutrition in Ascobolus furfuraceus. Sources of nitrogen]

The effect of various nitrogen sources on growth and efficiency parameters of Ascobolus furfuraceus was investigated. As nitrogen sources, sodium nitrate and nitrite, inorganic ammonium salts and nitrated organic compounds have been used. The results showed that all of them could be used by the fungus, with the exceptions of sodium nitrite and ammonium oxalate. Good correlation was observed among the growth parameters, the ’economic coefficients’ of uptake and internal conversion of sources, and the specific respiration rates. The best nitrogen source - estimated as growth and efficiency parameters - was ammonium carbonate in the culture conditions used. The possibility of heterotrophic carbon fixation is discussed.

[Kinetics of glucose incorporation and morphological variation of the mycelia of Ascobolus furfuraceus]. / Cinética de incorporación de glucosa y variación morfológica del micelio de Ascobolus furfuraceus.

Mycelium of Ascobolus furfuraceus Pers. p. Hook (Ascomycetes-Pezizales) was grown in liquid medium for 13 days; at this point it was fed with either 15 mg ml-1 glucose of fresh liquid medium. The kinetics of glucose uptake after re-feeding is correlated with the differentiation of globose vesicles which grew from single intercalary cells of the hyphae. These vesicles seem to be glycogen store structures as shown by the iodine reaction.

Cinetica de incorporacion de glucosa y variacion morfologica del micelio de Ascobolus furfuraceus. / Kinetics of glucose uptake and morphological changes of the mycelium of Ascobulus furfuraceus

La cinetica de incorporacion de glucosa por el micelio de Ascobolus furfuraceus de 13 dias de crecimiento y realimentado con glucosa o con medio fresco total, esta en correlacion con la diferenciacion progresiva de estructuras vesiculares que funcionarian como reservorio de glucogeno