30717 20150429092420.0 TAZ-TFG-2015-011 eng ROMEO OLIVÁN, ANA CARACTERIZACIÓN Y EXTRACCIÓN DE LA LISOZIMA DE LA CLARA DE HUEVO Zaragoza Universidad de Zaragoza 2015 by-nc-sa Creative Commons 3.0 http://creativecommons.org/licenses/by-nc-sa/3.0/ Lysozyme is a small protein (14kDa) that occurs in almost all body fluids, and tissues of animal organisms. It exhibits bacteriolytic activity due to its ability of breaking bacterial cell walls. The demand of this enzyme has increased because of its diverse uses in pharmacy or food industry. Different methods for isolation have been proposed. Most of them are used in laboratory practice to obtain the pure enzyme of high activity, however only some of these methods are feasible on a commercial scale. The most useful method of lysozyme extraction are chromatography tecnhniques. Other methods, such as crystallization, aqueous two-phase extraction or membrane filtration, have also been reported. In this work, we studied a two-step protocol for the lysozyme extraction from chicken egg white, based on a protein precipitation coupled with chromatography. Three precipitation agents (polyethilenglycol, ammonium sulfate and sodium chloride) and four types of chromatography (cation-exchange chromatography, hydrophobic interaction chromatography, gel filtration chromatography and affinity chromatography) were assayed to determine the efficiency of each methodology. The most efficient methodology was the combination of protein precipitation using 3% polyethilenglycol and ion exchange chromatography, obtaining lysozyme of great purity and the activity was as high as 72 U/ml Graduado en Biotecnología Derechos regulados por licencia Creative Commons ENGIN, EVREN DORUK dir. Universidad de Zaragoza Bioquímica y Biología Molecular y Celular Bioquímica y Biología Molecular ANEL BERNAL, ALBERTO ponente 631550@celes.unizar.es 1003651 http://zaguan.unizar.es/record/30717/files/TAZ-TFG-2015-011.pdf Memoria (eng) Memoria (eng) oai:zaguan.unizar.es:30717 driver trabajos-fin-grado deposita:2015-04-21 TAZ TFG CIEN