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1.
Enzyme Microb Technol ; 128: 9-21, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31186114

ABSTRACT

Silica has been extracted from rice husks via a simple hydrothermal process and functionalized with triethoxy(octyl)silane -OCTES (Octyl-SiO2) and (3-aminopropyl)triethoxysilane - 3-APTES (Amino-SiO2), with the aim of using it as support to immobilize lipase from Thermomyces lanuginosus (TLL) via adsorption. The supports have been characterized by particle size distribution and elemental analyses, XRD, TGA, SEM, AFM and N2 physisorption so as to confirm their functionalization. Effect of pH, temperature, initial protein loading and contact time on the adsorption process has been systematically evaluated. Maximum immobilized protein loading of 12.3 ± 0.1 mg/g for Amino-SiO2 (5 mM buffer sodium acetate at pH 4.0, 25 °C and initial protein loading of 20 mg/g) and 21.9 ± 0.1 mg/g for Octyl-SiO2 (5 mM buffer sodium acetate at pH 5.0, 25 °C and initial protein loading of 30 mg/g) was observed. However, these biocatalysts presented similar catalytic activity in olive oil emulsion hydrolysis (between 630 and 645 U/g). TLL adsorption was a spontaneous process involving physisorption. Experimental data on Octyl-SiO2 and Amino-SiO2 adsorption were well-fitted to the Langmuir isotherm model. It was also investigated whether these biocatalysts could synthesize cetyl esters via esterification reaction. Thus, it was found that cetyl stearate synthesis required 100-110 min of reaction time to attain maximum conversion percentage (around 94%). Ester productivity of immobilized TLL on Amino-SiO2 was 1.3-3.1 times higher than Octyl-SiO2.


Subject(s)
Adsorption , Enzymes, Immobilized/metabolism , Eurotiales/enzymology , Lipase/metabolism , Hydrogen-Ion Concentration , Hydrolysis , Kinetics , Lipase/isolation & purification , Olive Oil/metabolism , Oryza/chemistry , Silicon Dioxide/isolation & purification , Silicon Dioxide/metabolism , Temperature
2.
rev. udca actual. divulg. cient ; 21(2): 385-393, jul.-dic. 2018. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1094741

ABSTRACT

ABSTRACT Colombian flower growers are faced with economic and social problems, so they are looking for alternatives, which include Proteas, ornamentals that require research that ensures an appropriate, local technical management. One of the Proteas most likely to be involved in this search is the genus Leucadendron. Therefore, this study aimed to establish the best basis for rooting its cuttings. The experimental design was a split plot design with a factorial arrangement. Four substrates were evaluated in combination with two auxins, naphthaleneacetic acid (NAA) and indolebutiric acid (IBA), three doses each, plus a commercial control. Each treatment was repeated three times and the experimental unit consisted of 30 stakes at the first locality and 25 at the second one. The most relevant results showed that vermiculite was the best substrate for rooting cuttings of Leucadendron at both localities. Also, it was identified that IBA is the growth regulator which improved the rooting percentage, the root volume, the stem decreased the percentage of losses.


RESUMEN Los cultivadores colombianos de flores tradicionales están confrontados con problemas, tanto económicos como sociales, por lo que están buscando alternativas, que incluyen a las Proteas, ornamentales que requieren investigación, que asegura un manejo técnico. Una de las Proteas con más posibilidad de estar involucrado en este desarrollo es el género Leucadendron. El diseño experimental empleado fue un diseño de parcelas, divididas con arreglo factorial. Así, que el objetivo de este estudio fue establecer la base para el enraizamiento de las estacas. En combinación con dos auxinas, ácido 1-naftalenacético (ANA) y ácido indolbutírico (AIB), tres dosis de cada una y el control comercial, se evaluaron cuatro sustratos. Cada tratamiento, se repitió tres veces y cada unidad experimental consistió en 30 estacas, para la primera localidad y de 25, para la segunda. Los resultados más relevantes mostraron que el mejor sustrato para el enraizamiento de estacas de Leucadendron fue la vermiculita, en ambas localidades. También, se identificó que AIB es el regulador de crecimiento que mejoró el porcentaje de enraizamiento, el volumen de raíces, la longitud del tallo disminuyó el porcentaje de pérdidas.

3.
Rev. Fac. Cienc. Vet ; 55(1): 42-52, jun. 2014. ilus, tab
Article in Spanish | LILACS | ID: lil-740408

ABSTRACT

Para determinar el efecto de dos tipos de material de cama sobre la carga parasitaria de cerdos en crecimiento y engorde alojados en cama profunda, se realizó un ensayo utilizando 92 cerdos machos inmunocastrados, con peso inicial promedio de 30 kg y 70 d de edad, hasta peso de finalización. Se utilizó un diseño completamente al azar, con dos tratamientos basados en el material de cama, heno de gramíneas (HG) y concha de arroz (CA), con seis réplicas y 46 animales/tratamiento distribuidos según una densidad de 1,37 cerdos/m². Se administró ad libitum un alimento comercial. Durante 90 d se evaluó la cantidad de material de cama requerido por animal (CCA), la humedad de la cama (HC), emisión de amonio (EAC), composición química de la cama, zonas de uso (% área limpia y sucia), presencia de ectoparásitos (PE), carga parasitaria en la cama (CPC) y heces de los cerdos (CPH). Los datos obtenidos fueron analizados utilizando el método PROC GENMOD del paquete estadístico SAS. Se encontraron diferencias significativas (P< 0,05) entre HG y CA, para las variables CCA (107,32 y 84,157 kg/animal/ciclo), EAC (9,462 y 3,3274 ppm), PE (14,04 y 4,34 moscas/animal/d), zonas de uso y composición química de la cama en sus fracciones de nitrógeno, proteína, fibra, grasa cruda, ceniza y fósforo. No se encontraron diferencias significativas para CPC, pero si para CPH. La CA presentó características de HC, EAC, CPH y zonas de uso más favorables que la HG. La presencia de ectoparásitos fue mayor en los cerdos alojados en cama con HG. Además, se requirió menor cantidad de material de cama por animal en CA comparado con HG.


To determine the effect of two types of bedding material on parasitic burden in growing and fattening pigs housed in deep litter, an assay was conducted using 92 immune castrated males, with an average initial weight of 30.00 kg and 70 days old until finalization weight. A completely randomized design was used, with two treatments based on bedding material, as follows: grass hay (GH) and rice husk (RH), with six replicates/treatment and 46 animals/treatment, according to a density of 1.37 pigs/m². A commercial feed was given ad libitum. During the course of 90 days was evaluated: amount of bedding material required per animal (ABA), bedding moisture (BM) ammonia emission (AE), chemical composition of the bed, areas of use (% of clean and dirty area), presence of ectoparasites (PE), parasite burden in bed (PBB) and feces of pigs (PBF). The data obtained were analyzed using the PROC GENMOD methodology, of the Statistical Analysis System (SAS). Statistically significant (P<0.05) differences were found between GH and RH for the variables ABA (107.32 and 84.157 kg/animal/cycle), AE (9.462 and 3.3274 ppm), PE (14.04, and 4.34 flies/animal/day), areas of use and chemical composition of the bed in their nitrogen, protein, fiber, crude fat, ash and phosphorus fractions:. No significant differences between treatments were found for PBB. In contrast, significant differences were shown for PBF. The presence of ectoparasites in pigs housed in deep litter with HG was greater. Additionally, a less amount of bed material was required per animal with RH, in comparison with HG.

4.
Acta biol. colomb ; 18(2): 365-374, May-Aug. 2013. ilus, tab
Article in Spanish | LILACS | ID: lil-685935

ABSTRACT

Se evaluó el desarrollo de plántulas de tomate (planta bioindicadora de toxicidad) en suelos con aserrín y cascarilla de arroz parcialmente biodegradados por Pleurotus Ostreatus bajo condiciones de invernadero. Se determinaron los componentes orgánicos (carbono, celulosa, lignina, extraíbles y materia orgánica) e inorgánicos (nitrógeno, fósforo y pH) antes y después de inocular el hongo en el aserrín y la cascarilla de arroz. Se realizaron mezclas de cada sustrato con un suelo pobre en nutrientes en proporciones iguales (1:1) y se les determinó el porcentaje de humedad. El experimento estuvo constituido por un diseño completamente aleatorio, con dos grupos de seis tratamientos para cada sustrato, a los 30 días se determinaron los parámetros de crecimiento y desarrollo de las plántulas. Los sustratos biodegradados reportaron bajo contenido de C, N y P. El tratamiento aserrín biodegradado + suelo fertilizado (ASB + SF), presentó los mejores resultados en número de hojas (12,9), altura de las plantas (25,94 cm), longitud radical (5,92 cm), peso seco (0,138 g) y peso fresco (1,012 g). El sustrato ASB + SF puede funcionar como sustrato favorable para el cultivo de plántulas de tomate debido a que aporta los nutrientes necesarios para el buen crecimiento de las plántulas. En la cascarilla de arroz las plantas no crecieron adecuadamente para conseguir ser trasplantadas.


It was evaluated the development of tomato seedlings (plant bioindicator of toxicity) in soils with sawdust and rice husk partially biodegraded by Pleurotus Ostreatus in greenhouse conditions. Both organic compounds (carbon, cellulose, lignin, extractives, and organic matter), and inorganic compounds (nitrogen, phosphorus and pH) were determined, before and after fungus inoculation on sawdust and rice husk. Mixtures were held of each substrate with a nutrient poor soil in equal proportions (1:1) and the moisture content was determined. The experiment consisted of a completely randomized, with two groups of six treatments for each substrate, and 30 days later, parameters of growth and development were identified. Biodegraded substrates presented low C, N and P. BSA + SF treatment (biodegraded sawdust + fertilized soil) presented the best results in the number of leaves (12.9), plant height (25.94 cm), root length (5.92 cm), dry weight (0.138 g), and fresh weight (1.012 g). BSA + SF substrate can work as favorable substrate for growing tomato seedlings, BSA + SF substrate can work as favorable substrate for growing of tomato seedlings, since it provides the nutrients necessary for a good growth. Plants in rice bran did not grow adequately for transplanting.

5.
Article in English | VETINDEX | ID: vti-717924

ABSTRACT

Two experiments were carried out at the Poultry Sector of the School of Agrarian Sciences of the Federal University of Grande Dourados to evaluate the incidence of leg problems in broilers reared on two distinct types of bedding material: rice husks or wood shavings, both new and reused. In both trials, a randomized experimental design was applied in factorial arrangement (2 x 2 x 2) using two genetic strains (Cobb® or Ross®); two sexes (male or female), and two litter materials (rice husks or wood shavings). In each trial 1080 one day pullets were reared equally divided in the treatments. The birds were placed in 4.5 m² boxes at a density of 10 birds m-2. All birds were fed diets with equal nutritional density, and water was offered ad libitum. Feeds were divided in three phases: starter diet (1 - 21 days), grower diet (22 - 35 days), and finisher diet (36 - 45 days). On day 45, fifty birds were randomly selected in each experiment to evaluate flock leg problems. The following parameters were analyzed: gait score, incidence of valgus and varus disorder, footpad dermatitis, femoral degeneration, tibial dyschondroplasia, and spondylolisthesis. Ambient temperature during rearing and litter caking and moisture content were recorded in four boxes per treatment. The analytical hierarchy process was used to organize the data into specific criteria. Several criteria, related to the attributes that were determinant according to the statistical analysis, were chosen in order to provide the best input to the process. Results indicated that new wood-shavings bedding was the most appropriate bedding to prevent locomotion problems, followed by new rice husks, reused wood shavings, and reused rice husks. However, when leg problems were associated to sex and genetic strain, male Ross birds strain presented less problems when reared on new rice husks, followed by new wood shavings

6.
Article in English | LILACS-Express | VETINDEX | ID: biblio-1489916

ABSTRACT

Two experiments were carried out at the Poultry Sector of the School of Agrarian Sciences of the Federal University of Grande Dourados to evaluate the incidence of leg problems in broilers reared on two distinct types of bedding material: rice husks or wood shavings, both new and reused. In both trials, a randomized experimental design was applied in factorial arrangement (2 x 2 x 2) using two genetic strains (Cobb® or Ross®); two sexes (male or female), and two litter materials (rice husks or wood shavings). In each trial 1080 one day pullets were reared equally divided in the treatments. The birds were placed in 4.5 m² boxes at a density of 10 birds m-2. All birds were fed diets with equal nutritional density, and water was offered ad libitum. Feeds were divided in three phases: starter diet (1 - 21 days), grower diet (22 - 35 days), and finisher diet (36 - 45 days). On day 45, fifty birds were randomly selected in each experiment to evaluate flock leg problems. The following parameters were analyzed: gait score, incidence of valgus and varus disorder, footpad dermatitis, femoral degeneration, tibial dyschondroplasia, and spondylolisthesis. Ambient temperature during rearing and litter caking and moisture content were recorded in four boxes per treatment. The analytical hierarchy process was used to organize the data into specific criteria. Several criteria, related to the attributes that were determinant according to the statistical analysis, were chosen in order to provide the best input to the process. Results indicated that new wood-shavings bedding was the most appropriate bedding to prevent locomotion problems, followed by new rice husks, reused wood shavings, and reused rice husks. However, when leg problems were associated to sex and genetic strain, male Ross birds strain presented less problems when reared on new rice husks, followed by new wood shavings

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