899 resultados para inoculum sources


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Aspergillus phoenicis is an interesting heat tolerant fungus that can synthesize enzymes with several applications in the food industry due to its great hydrolytic potential. In this work, the fungus produced high enzymatic levels when cultivated on inexpensive culture media consisting of flakes from different origins such as cassava flour, wheat fibre, crushed soybean, agro-industrial wastes, starch, glucose or maltose. Several enzymatic systems were produced from these carbon sources, but amylase was the most evident, followed by pectinase and xylanase. Traces of CMCases, avicelase, lipase, β-xylosidase, β-glucosidase and α-glucosidase activities were also detected. Amylases were produced on rye flakes, starch, oat flakes, corn flakes, cassava flour and wheat fibre. Significant amylolytic levels were produced in the culture medium with glucose or when this sugar was exhausted, suggesting an enzyme in the constitutive form. Cassava flour, rye, oats, barley and corn flakes were also used as substrates in the hydrolytic reactions, aiming to verify the liberation potential of reducing sugars. Corn flakes induced greater liberation of reducing sugars as compared to the others. Thin layer chromatography of the reaction end products showed that the hydrolysis of cassava flour liberated maltooligosaccharides, but cassava flour and corn, rye, oats and barley flakes were hydrolyzed to glucose. These results suggested the presence of glucoamylase and α-amylase as part of the enzymatic pool of A. phoencis.

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Abstract Background The study and analysis of gene expression measurements is the primary focus of functional genomics. Once expression data is available, biologists are faced with the task of extracting (new) knowledge associated to the underlying biological phenomenon. Most often, in order to perform this task, biologists execute a number of analysis activities on the available gene expression dataset rather than a single analysis activity. The integration of heteregeneous tools and data sources to create an integrated analysis environment represents a challenging and error-prone task. Semantic integration enables the assignment of unambiguous meanings to data shared among different applications in an integrated environment, allowing the exchange of data in a semantically consistent and meaningful way. This work aims at developing an ontology-based methodology for the semantic integration of gene expression analysis tools and data sources. The proposed methodology relies on software connectors to support not only the access to heterogeneous data sources but also the definition of transformation rules on exchanged data. Results We have studied the different challenges involved in the integration of computer systems and the role software connectors play in this task. We have also studied a number of gene expression technologies, analysis tools and related ontologies in order to devise basic integration scenarios and propose a reference ontology for the gene expression domain. Then, we have defined a number of activities and associated guidelines to prescribe how the development of connectors should be carried out. Finally, we have applied the proposed methodology in the construction of three different integration scenarios involving the use of different tools for the analysis of different types of gene expression data. Conclusions The proposed methodology facilitates the development of connectors capable of semantically integrating different gene expression analysis tools and data sources. The methodology can be used in the development of connectors supporting both simple and nontrivial processing requirements, thus assuring accurate data exchange and information interpretation from exchanged data.

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Hundred forty-four Shaver White laying hens were used over a 4 week experimental period to investigate the effect of 3% of soybean oil, corn oil (MIL), canola oil, flaxseed oil (LIN), salmon oil (SAL) or tuna and sardine oil (SR/AT) added to the diets, upon the fatty acid egg yolk composition, blood plasma levels and incorporation time of each fatty acid into the egg yolk. Hens were allocated into 72 cages and the experimental design was a 6 x 6 randomized factorial model. Hens fed 3% of different oils, responded with increased polyunsaturated fatty acids omega 3 (ω-3 PUFAs), except for corn oil. The addition of flaxseed, soybean or corn oil into the diet increased the PUFAs levels into the egg yolk and in the blood plasma. Adding tuna and sardine oil into the diet increased the concentration of yolk saturated fatty acids. The levels of ω-3 PUFAs were increased in the tuna and sardine oil treatment, while the flaxseed oil increased the plasma fatty acids. The deposition of 349.28 mg/yolk of a-linolenic fatty acids (ALA) was higher in the group fed LIN, while the higher equal to 157.13 mg DHA/yolk was observed in group SR/AT. In the plasma, deposition increased from 0.33% (MIL) for 6.29% ALA (LIN), while that of DHA increase of 0.47% (MIL) for 4.24% (SAL) and 4.48% (SR/AT) and of 0.98% (MIL) for 6.14% (SR/AT) and 8.44% (LIN) of ω-3 PUFAs. The percentage of EPA into the yolk and plasma was higher for the hens fed 3% tuna and sardine oil diet, as well as the levels of yolk DHA. The concentration of DHA into the plasma was higher for the salmon and tuna/sardine oil treatments. The PUFAs yolk decreased during the first eight days of experiment, while the ω-3 PUFAs increased during the same period. The concentration of ALA increased until ten days of experiment, while the percentage of EPA and DHA increased up to the eighth experimental day

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Two hundred eighty-eight 32-wk-old Hisex White laying hens were used in this research during a 10 weeks period, arranged in a 2 x 5 completely randomized factorial design, with three replicates of eight birds per treatment. Two groups: fish oil (OP) and Marine Algae (AM) with five DHA levels (120, 180, 240, 300 and 360 mg/100 g diet) were assigned including two control groups birds fed corn and soybean basal diet (CON) and a diet supplemented with AM (AM420) to study the effect of time 0, 2, 4, 6 and 8 weeks (wk) on the efficiency of egg yolk fatty acid enrichment. The means varied (p<0.01) of 17.63% (OP360) to 22.08% (AM420) is the total Polyunsaturated Fatty Acids (PUFAs) and 45.8 mg/g (OP360), 40.37 mg/g (OP360, 4 wk) to 65.82 mg/g (AM420) and 68.79 mg/g/yolk (AM120, 8 wk) for n-6 PUFAs. On the influence of sources and levels in the times, the means of n-3 PUFAs increased by 5.58 mg/g (AM120, 2 wk) to 14.16 mg/g (OP360, 6 wk) when compared to average of 3.34 mg PUFAs Ω/g/yolk (CON). Usually, the means DHA also increased from 22.34 (CON) to 176.53 mg (μ, OP360), 187.91 mg (OP360, 8 wk) and 192.96 mg (OP360, 6 wk) and 134.18 mg (μ, OP360), 135.79 mg (AM420, 6 wk), 149.75 mg DHA (AM420, 8 wk) per yolk. The opposite was observed for the means AA, so the effect of the sources, levels and times, decreased (P <0.01) of 99.83 mg (CON) to 31.99 mg (OP360, 4 wk), 40.43 mg (μ, OP360) to 61.21 mg (AM420) and 71.51 mg AA / yolk (μ, AM420). Variations of the average weight of 15.75g (OP360) to 17.08g (AM420) yolks of eggs de 32.55% (AM420) to 34.08% (OP360) of total lipids and 5.28 g (AM240) to 5.84 g (AM120) of fat in the yolk were not affected (p>0.05) by treatments, sources, levels and times studied. Starting of 2 week, the hens increased the level of n-3 PUFAs in the egg yolks, being expressively increased (p<0.01) until 4 weeks, which after the increased levels of n-3 PUFAs tended to if stabilize around of time of 8 experimental weeks, when it was more effective saturation of the tissues and yolk.

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We prove a uniqueness result related to the Germain–Lagrange dynamic plate differential equation. We consider the equation {∂2u∂t2+△2u=g⊗f,in ]0,+∞)×R2,u(0)=0,∂u∂t(0)=0, where uu stands for the transverse displacement, ff is a distribution compactly supported in space, and g∈Lloc1([0,+∞)) is a function of time such that g(0)≠0g(0)≠0 and there is a T0>0T0>0 such that g∈C1[0,T0[g∈C1[0,T0[. We prove that the knowledge of uu over an arbitrary open set of the plate for any interval of time ]0,T[]0,T[, 0

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We derive lower bounds on the density of sources of ultra-high energy cosmic rays from the lack of significant clustering in the arrival directions of the highest energy events detected at the Pierre Auger Observatory. The density of uniformly distributed sources of equal intrinsic intensity was found to be larger than ~(0.06 - 5) × '10 POT. -4' 'Mpc POT. -3' at 95% CL, depending on the magnitude of the magnetic deflections. Similar bounds, in the range (0.2 - 7) × '10 POT. -4' 'Mpc POT. -3', were obtained for sources following the local matter distribution.

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Aerosol particles are likely important contributors to our future climate. Further, during recent years, effects on human health arising from emissions of particulate material have gained increasing attention. In order to quantify the effect of aerosols on both climate and human health we need to better quantify the interplay between sources and sinks of aerosol particle number and mass on large spatial scales. So far long-term, regional observations of aerosol properties have been scarce, but argued necessary in order to bring the knowledge of regional and global distribution of aerosols further. In this context, regional studies of aerosol properties and aerosol dynamics are truly important areas of investigation. This thesis is devoted to investigations of aerosol number size distribution observations performed through the course of one year encompassing observational data from five stations covering an area from southern parts of Sweden up to northern parts of Finland. This thesis tries to give a description of aerosol size distribution dynamics from both a quantitative and qualitative point of view. The thesis focuses on properties and changes in aerosol size distribution as a function of location, season, source area, transport pathways and links to various meteorological conditions. The investigations performed in this thesis show that although the basic behaviour of the aerosol number size distribution in terms of seasonal and diurnal characteristics is similar at all stations in the measurement network, the aerosol over the Nordic countries is characterised by a typically sharp gradient in aerosol number and mass. This gradient is argued to derive from geographical locations of the stations in relation to the dominant sources and transport pathways. It is clear that the source area significantly determine the aerosol size distribution properties, but it is obvious that transport condition in terms of frequency of precipitation and cloudiness in some cases even more strongly control the evolution of the number size distribution. Aerosol dynamic processes under clear sky transport are however likewise argued to be highly important. Southerly transport of marine air and northerly transport of air from continental sources is studied in detail under clear sky conditions by performing a pseudo-Lagrangian box model evaluation of the two type cases. Results from both modelling and observations suggest that nucleation events contribute to integral number increase during southerly transport of comparably clean marine air, while number depletion dominates the evolution of the size distribution during northerly transport. This difference is largely explained by different concentration of pre-existing aerosol surface associated with the two type cases. Mass is found to be accumulated in many of the individual transport cases studied. This mass increase was argued to be controlled by emission of organic compounds from the boreal forest. This puts the boreal forest in a central position for estimates of aerosol forcing on a regional scale.

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[EN] Background: Culicoides (Diptera: Ceratopogonidae) biting midges are vectors for a diversity of pathogens including bluetongue virus (BTV) that generate important economic losses. BTV has expanded its range in recent decades, probably due to the expansion of its main vector and the presence of other autochthonous competent vectors. Although the Canary Islands are still free of bluetongue disease (BTD), Spain and Europe have had to face up to a spread of bluetongue with disastrous consequences. Therefore, it is essential to identify the distribution of biting midges and understand their feeding patterns in areas susceptible to BTD. To that end, we captured biting midges on two farms in the Canary Islands (i) to identify the midge species in question and characterize their COI barcoding region and (ii) to ascertain the source of their bloodmeals using molecular tools.Methods: Biting midges were captured using CDC traps baited with a 4-W blacklight (UV) bulb on Gran Canaria and on Tenerife. Biting midges were quantified and identified according to their wing patterns. A 688 bp segment of the mitochondrial COI gene of 20 biting midges (11 from Gran Canaria and 9 from Tenerife) were PCR amplified using the primers LCO1490 and HCO2198. Moreover, after selected all available females showing any rest of blood in their abdomen, a nested-PCR approach was used to amplify a fragment of the COI gene from vertebrate DNA contained in bloodmeals. The origin of bloodmeals was identified by comparison with the nucleotide-nucleotide basic alignment search tool (BLAST). Results: The morphological identification of 491 female biting midges revealed the presence of a single morphospecies belonging to the Obsoletus group. When sequencing the barcoding region of the 20 females used to check genetic variability, we identified two haplotypes differing in a single base. Comparison analysis using the nucleotide-nucleotide basic alignment search tool (BLAST) showed that both haplotypes belong to Culicoides obsoletus, a potential BTV vector. As well, using molecular tools we identified the feeding sources of 136 biting midges and were able to confirm that C. obsoletus females feed on goats and sheep on both islands.Conclusions: These results confirm that the feeding pattern of C. obsoletus is a potentially important factor in BTV transmission to susceptible hosts in case of introduction into the archipelago. Consequently, in the Canary Islands it is essential to maintain vigilance of Culicoides-transmitted viruses such as BTV and the novel Schmallenberg virus.

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[EN] The expression and regulation of intestinal oligopeptide transporter (PepT)-1 when vegetable sources are used as a substitute for fish meal in the diet of marine fish has not yet been explored. In the present study, as part of our ongoing work on elucidating PepT1 gene expression in relation to different dietary treatments, we have now isolated and deposited in Genbank database (accession no. GU733710) a cDNA sequence representing the PepT1 in the sea bream (Sparus aurata). The ?de novo? prediction of the three-dimensional structure of PepT1 protein is presented. We also analyzed diet-induced changes in the expression of PepT1 mRNA via real-time RT-PCR using the standard curve method. Sea bream were fed for 140 days with one of the following four diet formulations (43% protein/21% lipid): a control fast growth-promoting diet (C), and three diets with the same formulation but in which 15% of the fish meal was substituted by protein concentrates either from lupine (LPC), chick pea (CPC), or green pea (PPC). Fish fed PPC had significantly (p < 0.05) lower levels of PepT1 transcripts in the proximal intestine than the controls, whereas PepT1 transcript levels in fish fed LPC or CPC were not significantly different from the controls. Although growth was similar between fish fed with different diets during the first 72 days of feeding, growth of the fish fed with PPC was reduced during the second part of the trial and was significantly (p < 0.05) lower than fish fed LPC and CPC diets by the end of the experiment. Correlation between these results and fish growth performances highlights that the intestinal PepT1 mRNA level may serve as a useful marker of the dietary protein quality and absorption efficiency.

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Máster Universitario International en Acuicultura. Trabajo presentado como requisito parcial para la obtención del Título de Máster Universitario Internacional en Acuicultura, otorgado por la Universidad de Las Palmas de Gran Canaria (ULPGC), el Instituto Canario de Ciencias Marinas (ICCM), y el Centro Internacional de Altos Estudios Agronómicos Mediterráneos de Zaragoza (CIHEAM)

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The bioproduction of materials and energy from renewable sources (industrial biotechnology) is getting more and more interest in order to improve environmental sustainability of chemical industrial processes and to decrease their dependence from oil. Anaerobic digestion of organic waste matrices (agricultural and industrial wastes, organic fraction of municipal wastes, sewage sludges etc.) may play an important role in the implementation of industrial biotechnology being a well developed strategy in the valorization of complex matrices, as it can mineralize them while producing bioenergy in the form of a biogas rich in methane. In this research the potential of anaerobic digestion in the treatment of polluted sewage sludge was studied by developing three set of anaerobic microcosms with sludges differently contaminated by xenobiotic compounds. The effect of different incubating temperatures and of exogenous carbon and vitamine sources was investigated along with the role of the occurring microbial populations in the pollutant degradation activity. So, while confirming the potential of anaerobic digestion for the biomethanization of sewage sludges, this work proved the effectiveness of this technology in the removal of pollutants too. Moreover, since the degradation of lignocellulose appears to be a limiting step in the anaerobic treatment of a wide range of biomass, the possibility of optimizing anaerobic digestion of lignocellulosic substrates was also studied. To this aim a research was carried out at the BOKUUniversity of Natural Resources and Applied Life Sciences, Department for Agrobiotechnology, IFA - Tulln, where mixed cellulolytic cultures were isolated from biogas plants while assessing the metabolic pathway leading to cellulose degradation and verifying their capability to grow on lignocellulose too, proving that on the long term such bacterial cultures could be used as inoculum in order to improve the hydrolysis of lignocellulose in anaerobic digestion plants.