Molecular Techniques for Dicistrovirus Detection without RNA Extraction or Purification

Dicistroviridae is a new family of small, nonenveloped, and +ssRNA viruses pathogenic to both beneficial arthropods and insect pests as well. Triatoma virus (TrV), a dicistrovirus, is a pathogen of Triatoma infestans (Hemiptera: Reduviidae), one of the main vectors of Chagas disease. In this work, we report a single-step method to identify TrV, a dicistrovirus, isolated from fecal samples of triatomines. The identification method proved to be quite sensitive, even without the extraction and purification of RNA virus.

Lignin extraction, purification and depolymerization study

280 p. : il.

Uncovering Ecosystem Service Bundles through Social Preferences

11 p.

Fraccionamiento del licor gastado en pasteado al sulfito ácido mediante ultrafiltración

Lignosulphonates (LS) and fermentable sugars are the main components of spent sulphite liquors (SSL) produced in acid sulphite pulping. In spite of different methods have been used for spent liquor fractionation such as precipitation or vaporization; membrane technology allows the separation of these components from the SSL due to their different size molecular weight, offering great advantages with regards to the traditionally methods (less energy consumption, high selective separation, and many others). In the present study, ceramic membranes with different cut-offs (15 kDa, 5 kDa and 1 kDa) were used to achieve the sugar purification and the LS concentration. The membranes were evaluated according to their efficacy and efficiency properties. Different series system were tested in order to improve the aptitudes of a singular membrane. The system with the three membranes in series (15, 5 and 1 kDa respectively) obtained the most purified permeate stream, referred to the sugar content. Also, a characterisation of the LS contained in the different streams produced in this system was carried out in order to know in a more precise manner the valorisation potential of these components by means of biorefinery processes.

TRANSFER OF ANALYTICAL METHODS FOR THE CHARACTERISATION OF NATURAL PRODUCTS TO R&D PROCESSES OF IDOKI

IDOKI SCF Technologies S.L. is a technology-based company, set up on September 2006 in Derio (Biscay) with the main scope of developing extraction and purification processes based on the use of supercritical fluid extraction technology (SFE) in food processing, extraction of natural products and the production of personal care products. IDOKI¿s researchers have been working on many different R&D projects so far, most of them using this technology. However, the optimization of a SFE method for the different matrices cannot be performed unless we have an analytical method for the characterisation of the extracts obtained in each experiment. The analytical methods are also essential for the quality control of the raw materials that are going to be used and also for the final product. This PhD thesis was born to tackle this problem and therefore, it is based on the development of different analytical methods for the characterisation of the extracts and products. The projects that we could include in this thesis were the following: the extraction propolis, the recovery of agroindustrial residues (soy and wine) and the dealcoholisation of wine.On the one hand, for the extraction of propolis, several UV-Vis spectroscopic methods were used in order to measure the antioxidant capacity and the total polyphenol and flavonoid content of the extracts. A SFC method was also developed in order to measure more specific phenolic compounds. On the other hand, for the recovery of agroindustrial residues UV-Vis spectroscopy was used to determine the total polyphenol content and two SFC methods were developed to analyse different phenolic compounds. Extraction methods such as MAE, FUSE and rotary agitation were also evaluated for the characterisation of the raw materials.Finally, for the dealcoholisation of wine, the development of a SBSE-TD-GC-MS and DHS-TD-GC-MS methods for the analysis of aromas and a NIR spectroscopic method for the determination of ethanol content with the help of chemometrics was necessary. Most of these methods are typically used in IDOKI¿s lab as routine analyses apart from others not included in this PhD thesis.

Reutilización de escoria negra de acería como soporte en biofiltros para la eliminación de H2S del biogás.

[EN]Due to the limitations associated with fossil fuels it is necessary to promote energy sources that are renewable as well as eco-friendly, such as biogas generated in anaerobic digesters. The biogas, composed principally of methane and CO2, is the result of the biodegradation of organic matter under anaerobic conditions. Its use as fuel is limited by the presence of minority compounds such as hydrogen sulphide (H2S); therefore, its pre-treatment is necessary. Currently there are various technologies for the removal of H2S from a gas stream, but most of them are based on physic-chemical treatments which have a number of drawbacks as reactive consumption, generation of secondary flows, etc. Biofiltration has been used as an efficient and low cost alternative to conventional purification processes, and excellent results for the degradation of H2S have been obtained. However process can be limited due to the progressive ageing of the support material, along with the loss of nutrients and other specific characteristics necessary for the good development of biomass. The purpose of this project is to develop a mixed support consisting of a mixture of an organic material and an inorganic support for its application in the removal of the H2S from biogas. This support material helps to optimize the characteristics of the bed and extend its lifespan. The development of such material will contribute to the implementation of biofiltration for treating biogas from anaerobic digesters for its use as biofuel. The inorganic material used is electric arc furnace (EAF) black slag, a by-product generated in large quantities in the production of steel in the Basque Country. Although traditionally the slag has been used in civil engineering, its physicochemical characteristics make it suitable for reuse as a filter medium in biofiltration. The main conclusion drawn from the experimental results is that EAF black slag is a suitable co-packing material in organic biofilters treating H2S-polluted gaseous streams. High pollutant removal rates have been achieved during the whole experimental period. The removal capacity recorded in biofilters with less inorganic material was higher than in those with higher slag portion. Nevertheless, all the biofilters have shown a satisfactory response even at high inlet loads (48 g·m-3·h-1), where the RE has not decreased over 82%.

Revisión bibliográfica del tratamiento de biogás por biofiltración.

[ES]En el siguiente trabajo se ha realizado una revisión bibliográfica en la que se muestran los resultados obtenidos al llevar a cabo la purificación del biogás y/o la eliminación del metano, en los casos en los que su valorización no sea posible, mediante métodos biológicos (biofiltración). Se recogen asimismo las diversas fuentes desde las que se genera el biogás (generación incontrolada o producción controlada) junto con las concentraciones típicas de todos los compuestos que pueden formar su composición. En la purificación del biogás se ha estudiado la eliminación de compuestos perjudiciales para el aprovechamiento energético del biogás, como son el sulfuro de hidrógeno (H2S), los mercaptanos y los siloxanos. Para el estudio de los compuestos a eliminar se ha diferenciado entre distintas configuraciones de biorreactores (biofiltros, biofiltros percoladores y biolavadores) y para cada una de ellas se han recogido datos representativos como la temperatura óptima de operación, las diferencias entre operar a pH ácido o básico (teniendo en cuenta que el pH natural de operación es ácido pero que en estas condiciones la solubilidad del H2S es menor y el relleno se deteriora con mayor rapidez). También se ha analizado la influencia de la cantidad de oxígeno necesario para garantizar la degradación total de los contaminantes y evitar la acumulación de depósitos de azufre, llegando incluso a necesitarse proporciones de O2/H2S de 49.2 para la oxidación completa del H2S. Se ha estudiado también la cantidad necesaria de nitrógeno (nutriente) en los procesos llevados a cabo en condiciones anaerobias (cercana a 200 mgN-NO3 -/L), así como el efecto que tienen los compuestos producidos en la oxidación parcial (azufre elemental (S0), metanol, formaldehido, etc.) en el funcionamiento del sistema.