32 research outputs found
Hidrolisado proteico de peixe em dietas para pós-larvas de tilápia-do-nilo
The objective of this work was to determine the apparent digestibility coefficient (ADC) of crude protein, crude energy, fat, and dry matter of fish protein hydrolysate (FPH), made of by-products of Nile tilapia (Oreochromis niloticus) and whole sardines (Cetengraulis edentulus), and to evaluate the productive performance and muscle fiber growth of Nile tilapia post-larvae. Two trials were conducted, the first one to determine the digestibility in 120 fingerlings (70.0±2.0 g), and the second one to evaluate the productive performance of 375 post-larvae, with three days of age, which were distributed in 25 aquaria with 30 L of useful volume. Five diets were prepared based on vegetable ingredients, to which fish were included at 0, 2, 4, 6, and 8% FPH. For the evaluation of muscle growth, eight fish of each experimental unit were used. The ADC values found were: 98.29% for dry matter; 99.28% for crude protein; and 99.13% for gross energy. The best zootechnical response for the productive performance resulted from the treatment with the inclusion of fish hydrolysate at 4.75%. The diets affected the frequency of the muscle fiber diameters, mainly the growth by hyperplasia. FPH can be efficiently used, and its inclusion at 4.75% is indicated in the diets for Nile tilapia in the post-larvae stage.O objetivo deste trabalho foi determinar o coeficiente de digestibilidade aparente (CDA) da proteÃna bruta, da energia bruta, da gordura e da matéria seca de um hidrolisado proteico de peixe (HPP), feito de resÃduos de tilápia-do-nilo (Oreochromis niloticus) e sardinha inteira (Cetengraulis edentulus), e avaliar o desempenho produtivo e o crescimento das fibras musculares de pós-larvas de tilápia-do-nilo. Realizaram-se dois ensaios, o primeiro para a determinação da digestibilidade em 120 alevinos (70,0±2,0 g) e, o segundo, para avaliação do desempenho produtivo de 375 pós-larvas, com três dias de idade, distribuÃdas em 25 aquários (unidade experimental) com volume útil de 30 L. Cinco rações à base de ingredientes vegetais foram elaboradas, à s quais se incluÃram os peixes a 0, 2, 4, 6 e 8% de HPP. Para a avaliação do crescimento muscular, oito peixes de cada unidade experimental foram utilizados. Os valores de CDA encontrados foram: 98,29% para matéria seca; 99,28% para proteÃna bruta; e 99,13% para energia bruta. As melhores respostas zootécnicas quanto ao desempenho produtivo resultaram do tratamento com a inclusão do hidrolisado proteico a 4,75%. As dietas influenciaram a frequência do diâmetro das fibras musculares, principalmente o crescimento por hiperplasia. O HPP pode ser eficientemente utilizado, e sua inclusão a 4,75% é indicada em dietas de tilápia-do-nilo na fase de pós-larva
Biochemical and thermodynamic characteristics of a new serine protease from Mucor subtilissimus URM 4133
A protease from the fungus Mucor subtilissimus URM 4133, capable of producing bioactive peptides from goat casein, was purified. SDS-PAGE and zymography showed a molecular mass of 30 kDa. The enzyme was active and stable in a wide pH range (6.0–10.5) and (5.0–10.5), respectively. Optimum temperature was at 45–50 °C and stability was above 80 % (40 °C/2 h). Activity was not influenced by ions or organic substances (Triton, Tween, SDS and DMSO), but was completely inhibited by PMSF, suggesting that it belongs to the serine protease family. The Km and Vmax were 2.35 mg azocasein.mL-1 and 333.33 U.mg protein-1, respectively. Thermodynamic parameters of irreversible denaturation (40–60 °C) were enthalpy 123.63 – 123.46 kJ.mol-1, entropy 120.24–122.28 kJ.mol-1 and Gibbs free energy 85.97 – 82.45 kJ.mol-1. Any peptide sequences compatible with this protease were found after analysis by MALDI-TOF, which suggests that it is a new serine protease.info:eu-repo/semantics/publishedVersio
Efeito Pesticida de Ésteres de Sacarose Sobre Calacarus heveae Feres (Acari: Eriophyidae) em Dois Clones de Seringueira
Sucrose esters are biodegradable, non pollutant and safe for health; moreover, they have shown great potential in the pest control. We tested a crude mix of sucrose esters on the survivorship and oviposition of Calacarus heveae Feres (Acari: Eriophyidae) females, an important rubber tree pest mite. The females were collected from rubber leaflets of the GT 1 and RRIM 600 clones. The mites were kept on stock arenas placed in rearing chamber at 28 + 0,1°C, 80 + 10% of relative humidity and 12h of light phase about two weeks before the assays. After this period, the mites were transferred to assay arenas made with leaflets from the same clone of stock arenas. The survivorship of females sprayed with sucrose esters in the concentrations of 1, 2, 3 and 4 g/L and their oviposition effect with 0.5 and 1 g/L were analyzed. The mites sprayed with 4 g/L had about 80% of mortality, while those with 1 g/L around 60%. All mites that died in the treatments with sucrose ester became dark with wrinkled tegument and decreased their body volume, suggesting dehydration. We also observed the efficacy of 1 g/L concentration to decrease the female oviposition in about 50%, in the third day after spraying. No differences were observed in the mortality and oviposition between females kept on both clones.Ésteres de sacarose são biodegradáveis, não poluem o ambiente e não causam danos a saúde, além de apresentarem potencial no controle de pragas. Foi testada a eficiência de uma mistura crua de ésteres de sacarose (sucroésteres) na sobrevivência e oviposição de fêmeas de Calacarus heveae Feres (Acari: Eriophyidae), uma importante praga da seringueira. As fêmeas foram provenientes de folÃolos dos clones de seringueira GT 1 e RRIM 600. Os ácaros foram mantidos nas arenas de estoque em câmara climatizada a 28 + 0,1°C, com umidade relativa de 80 + 10% e fotoperÃodo de 12 h, duas semanas antes dos ensaios. Após esse perÃodo, os ácaros foram transferidos para arenas de teste, confeccionadas com folÃolos dos mesmos clones das arenas de estoque. Foi avaliada a sobrevivência de fêmeas pulverizadas com sucroésteres nas concentrações de 1, 2, 3 e 4 g/L e o seu efeito na oviposição com as concentrações de 0,5 e 1 g/L. Os ácaros pulverizados com 4 g/L apresentaram mortalidade de cerca de 80%, enquanto os que receberam 1 g/L em torno de 60%. Todos os indivÃduos mortos pelo produto apresentaram murchamento do corpo e escurecimento do tegumento, como possÃvel causa da dessecação sofrida. Foi também verificada a eficiência da concentração de 1 g/L na redução da oviposição em torno de 50%, no terceiro dia após a pulverização. Não foram observadas diferenças na mortalidade e oviposição entre as fêmeas mantidas em ambos os clones estudados
Production and characterization of a milk-clotting protease in the crude enzymatic extract from the newly isolated Thermomucor indicae-seudaticae N31 (Milk-clotting protease from the newly isolated Thermomucor indicae-seudaticae N31)
Microbial rennet-like milk-clotting enzymes are aspartic proteinases that catalyze milk coagulation. substituting calf rennet. Crude enzymatic extract produced by the thermophilic fungus, Thermomucor indicae-seudaticae N31, on solid state fermentation (SSF) using wheat bran, exhibited high milk-clotting activity and low proteolytic activity after 24 h of fermentation. Highest milk-clotting activity (MCA) was at pH 5.7, at 70 degrees C and in 0.04 M CaCl(2); it was stable in the pH range 3.5-4.5 for 24 h and up to 45 degrees C for 1 h. MCA was highly inhibited by pepstatin A. Hydrolytic activity profile of the crude enzymatic extract on whole bovine casein, analyzed by gel electrophoresis (Urea-PAGE) and RP-HPLC revealed low proteolytic action towards casein fractions and a peptide profile similar to the one obtained with commercial Rhizomucor miehei protease (Hannilase). (C) 2009 Elsevier Ltd. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
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Temperature Tuning the Catalytic Reactivity of Cu-Doped Porous Metal Oxides with Lignin Models
Butanol synthesis from ethanol over CuMgAl mixed oxides modified with palladium (II) and indium (III)
Ethanol conversion to butanol was investigated over mixed oxides derived from hydrotalcites modified with copper, palladium or indium. The reaction was carried out in the 403–573 K temperature range using stainless steel reactors. The presence of indium or palladium in the catalyst influences the temperature of reaction so that it was possible obtain butanol at temperature as low as 423 K. This is in line with the fact that the addition of metals with high hydrogen-transfer capacity makes faster all steps of the reaction with great energy saving. The best selectivity to butanol (65%) was achieved using In-CuMgAl catalysts with 3% of ethanol conversion at a temperature as low as 443 K
Degradation of the Organochlorinated Herbicide Diuron by Rainforest Basidiomycetes
The main organochlorinated compounds used on agricultural crops are often recalcitrant, affecting nontarget organisms and contaminating rivers or groundwater. Diuron (N-(3,4-dichlorophenyl)-N′,N′-dimethylurea) is a chlorinated herbicide widely used in sugarcane plantations. Here, we evaluated the ability of 13 basidiomycete strains of growing in a contaminated culture medium and degrading the xenobiotic. Dissipation rates in culture medium with initial 25 mg/L of diuron ranged from 7.3 to 96.8%, being Pluteus cubensis SXS 320 the most efficient strain, leaving no detectable residues after diuron metabolism. Pycnoporus sanguineus MCA 16 removed 56% of diuron after 40 days of cultivation, producing three metabolites more polar than parental herbicide, two of them identified as being DCPU and DCPMU. Despite of the strong inductive effect of diuron upon laccase synthesis and secretion, the application of crude enzymatic extracts of P. sanguineus did not catalyzed the breakdown of the herbicide in vitro, indicating that diuron biodegradation was not related to this oxidative enzyme
Evaluation of the use of Syzygium cumini fruit extract as an antioxidant additive in orange juice and its sensorial impact
This work is an exploratory study of the possibility of promoting the consumption of Syzygium cumini fruit by adding its extract to orange juice making good use of its functional (antioxidant) properties. S. cumini fruit extract was characterized in terms of its anthocyanin content (2.11 g/100 g expressed in cyanidine-3-glucoside equivalents), total phenolic compounds (360 mg/100 g expressed in gallic acid equivalents) and antioxidant capacity evaluated by the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging method. The effects of the addition of S. cumini fruit crude extract as well as its chromatographic fractions on the juice were assessed chemically by headspace solid-phase micro-extraction and gas chromatography coupled with a mass spectrometry detector. Only six compounds had their chromatographic peak intensities clearly changed and the results are discussed in terms of the inhibition of the formation of 2-octanone, hexanol, alpha-copaene, and alpha-panasinsene and the conservation of octyl acetate and p-menth-1-en-9-ol. Sensory evaluation of orange juice with and without S. cumini crude extract addition did not show any significant differences in the sensorial profile, discriminative and acceptance tests.Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES
Temperature Tuning the Catalytic Reactivity of Cu-Doped Porous Metal Oxides with Lignin Models
Reported are the
temperature dependencies of the temporal product
evolution for lignin model compounds over copper-doped porous metal
oxide (CuPMO) in supercritical-methanol (sc-MeOH). These studies investigated
1-phenylethanol (PPE), benzyl phenyl ether (BPE), dihydrobenzofuran
(DHBF), and phenol over operating temperature ranges from 280 to 330
°C. The first three model compounds represent the β-O-4
and α-O-4 linkages in lignin as well as the furan group commonly
found in the β-5 linkage. Phenol was investigated due to its
key role in product proliferation as noted in earlier studies with
this Earth-abundant catalyst. In general, the apparent activation
energies for ether hydrogenolysis proved to be significantly lower
than that for phenol hydrogenation, a major side reaction leading
to product proliferation. Thus, temperature tuning is a promising
strategy to preserve product aromaticity as demonstrated by the more
selective conversion of BPE and PPE at lower temperatures. Rates of
methanol reforming over CuPMO were also studied over the temperature
range of 280–320 °C since it is this process that generates
the reducing equivalents for this catalytic system. In the absence
of substrate, the gaseous products H<sub>2</sub>, CO, and CO<sub>2</sub> were formed in ratios stoichiometrically consistent with catalyzed
methanol reformation and water gas shift reactions. The latter studies
suggest that the H<sub>2</sub> production ceases to be rate limiting
early in batch reactor experiments but also suggest that H<sub>2</sub> overproduction may contribute to product proliferation