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In this work, the induction of chitinases and β-1,3-glucanases was evaluated in the strain Vl-01 of Lecanicillyum lecanii (Zimm.) Zare & W. Gams in three culture media with different inductors: basal medium, basal medium supplemented with 0,5% of chitin, and basal medium supplemented with 0,2% of gelatin. The enzymatic activities were determined at 24, 72, 120, and 168 hours. The higher enzymatic levels of both chitinases and glucanases were obtained in the basal medium supplemented with gelatin. [ABSTRACT FROM AUTHOR]

Se realizaron dos experimentos, para evaluar enzimas (pectinasas, beta glucanasas y hemicelulasas) en dietas para pollos, sobre la digestibilidad ileal de proteína, aminoácidos esenciales (AA), EM y comportamiento productivo. En el Exp 1, se utilizaron 240 pollitos Ross 308 de 1 a 21 días en cuatros tratamientos: 1) Dieta testigo (sorgo+soya), 2) Dieta testigo+enzimas, 3) Dieta con menor contenido de nutrientes (7 % de PC, AA y EM) y 4) Como tratamiento 3+ enzimas. En el Exp 2, se utilizaron los mismos tratamientos del Experimento 1 en dietas en iniciación y finalización. Se emplearon 480 pollos Ross 308 de 1 a 49 días. En ambos experimentos, se utilizó arreglo factorial 2x2. Un factor fueron las dietas testigo sin y con reducción de nutrientes y otro factor con y sin la adición de enzimas. En el Exp 1, la ganancia de peso se afectó (P

Use of fungi of the Trichoderma genus for the biological control of pests and diseases is based, to a large extent, on their secretion of hydrolytic enzymes. The latter include chitinases and glucanases, which degrade the cell wall of phytopathogenic fungi as well as the cuticle of insects and nematodes. The aim of this study was to assess the induction dynamics of chitinases and glucanases in ten strains of Trichoderma spp. grown in liquid media with different inducers: basal medium, basal medium supplemented with 0.5% chitin and basal medium supplemented with 0.2% gelatin. Chitinase and glucanase activity were evaluated at the first, third, fifth and seventh day of culture. The highest values of chitinase activity were obtained in basal and basal media supplemented with chitin; β-1.3-glucanase, on the other hand, exhibited higher levels of activity in basal and basal media supplemented with gelatin. [ABSTRACT FROM AUTHOR]

Use of fungi of the Trichoderma genus for the biological control of pests and diseases is based, to a large extent, on their secretion of hydrolytic enzymes. The latter include chitinases and glucanases, which degrade the cell wall of phytopathogenic fungi as well as the cuticle of insects and nematodes. The aim of this study was to assess the induction dynamics of chitinases and glucanases in ten strains of Trichoderma spp. grown in liquid media with different inducers: basal medium, basal medium supplemented with 0.5% chitin and basal medium supplemented with 0.2% gelatin. Chitinase and glucanase activity were evaluated at the first, third, fifth and seventh day of culture. The highest values of chitinase activity were obtained in basal and basal media supplemented with chitin; β-1.3-glucanase, on the other hand, exhibited higher levels of activity in basal and basal media supplemented with gelatin. [ABSTRACT FROM AUTHOR]

Beauveria bassiana (Balsamo) Vuillemin is a promisoring biological control agent for invertebrate pests. In the development of a product based on a biological control agent, the study of the mode of action and the metabolites involved and their expression by the promissory strains is needed for selection, mass rearing, formulation and strain identity. The aim of this work was the biochemical characterization of six B. bassiana isolates by a time course experiment in different culture media. Mycelia disk of six B bassiana isolates were grown in a basal medium as the control, basal medium supplemented with chitin and basal medium supplemented with gelatine. Total proteins, chitinase and glucanase activities were assayed at 3, 5 and 7 days post inoculation. In general, isolates 33 and 9 showed the highest levels for all the parameters studied. The medium supplemented with chitin was the best for total protein and chitinase activity expression, while the media supplemented with gelatine was the best for glucanase production. [ABSTRACT FROM AUTHOR]

Trichoderma species fungi secret hydrolytic enzymes which allow them to penetrate the cell walls of phytopathogenic fungi. The glucanases are enzymes that hydrolyze the (3-glucans of the cell wall of phytopathogens such as Sclerotium rolfsii, Rhizoctonia solani and Pythium sp. The aim of this work was to carry out the dynamics of glucanase induction of ten Trichoderma spp. isolates evaluating the enzymatic activities at the first, third, fifth and seventh days of the cultures in three liquid media: basal medium, basal medium supplemented with chitin 0,5% and basal medium supplemented with gelatine 0,2%. The isolates 1, 13 y 17 reached the highest levels of glucanase specific activity during the induction with the basal medium supplemented with gelatine. The basal medium also resulted to be a good inductor of those enzymes. [ABSTRACT FROM AUTHOR]

The effect of addition of a commercial enzyme mixture (pectinases, â-glucanases and hemicellulases) to sorghum+soybean meal diets on apparent ileal amino acid and protein digestibility, metabolizable energy and productive performance in broiler was valuated with two experiments. Both experiments included four treatments: 1. Control, sorghum+soybean meal diet; 2. Control diet + enzymes; 3. Low-nutrient sorghum+soybean meal diet (7 % reduction in crude protein (CP), amino acids (AA) and metabolizable energy (ME); and 4. Low-nutrient diet + enzymes. A completely randomized design with a 2 x 2 factorial arrangement was used in both experiments; one factor was diets (control and low-nutrient) and the other factor was addition or not of enzymes. Exp 1 included 240 Ross 308 broiler chicks in a trial from 1 to 21 d of age, and Exp 2 included 280 Ross 308 chicks in a trial from 1 to 49 d of age. At 21 d in Exp 1, weight gain was lower (P<0.05) in the low-nutrient diets but mproved with addition of enzymes. Ileal amino acid digestibility and ME was best (3.0 % and 6.5 % respectively) in the low- nutrient diet with enzymes. At 49 d in Exp 2, weight gain was lower (P<0.05) in the low-nutrient diets but improved with addition of enzymes. Addition of the enzyme mixture improved the nutritional value of sorghum-soybean meal diets for broilers by increasing amino acid digestibility and metabolizable energy. This confirms the possibility of using enzymes to produce ower-cost feeds with adequate nutritional content and growth performance comparable to conventional feeds. [ABSTRACT FROM AUTHOR]

Peroxidase, phenylalanine ammonium lyase, glucanase and polyphenoloxidase activity was studied in rice varieties with different behaviours to the mite Steneotarsonemus spinki. For this propose, leaves were macerated in liquid nitrogen and enzymes were extracted with sodium acetate 0.1 M pH 5,2. Higher values of specific activities were obtained for the varieties that presented a higher tolerance behaviour against the mite. Varieties were grouped according to their susceptibility degree. [ABSTRACT FROM AUTHOR]

Use of fungi of the Trichoderma genus for the biological control of pests and diseases is based, to a large extent, on their secretion of hydrolytic enzymes. The latter include chitinases and glucanases, which degrade the cell wall of phytopathogenic fungi as well as the cuticle of insects and nematodes. The aim of this study was to assess the induction dynamics of chitinases and glucanases in ten strains of Trichoderma spp. grown in liquid media with different inducers: basal medium, basal medium supplemented with 0.5% chitin and basal medium supplemented with 0.2% gelatin. Chitinase and glucanase activity were evaluated at the first, third, fifth and seventh day of culture. The highest values of chitinase activity were obtained in basal and basal media supplemented with chitin; ß-1.3-glucanase, on the other hand, exhibited higher levels of activity in basal and basal media supplemented with gelatin.