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La microencapsulación de compuestos de actividad biológica (ADN, fármacos, proteínas, probióticos, enzimas, etc.), desde el punto de vista tecnológico, podría definirse como el proceso de recubrimiento de dichos compuestos, bajo la forma de moléculas, partículas sólidas o glóbulos líquidos, con materiales de distinta naturaleza, para dar lugar a partículas de tamaño micrométrico. Uno de los polímeros naturales más utilizados para la producción de microesferas es el quitosano (?-1,4- glucosamina). Diversos métodos han sido propuestos para la producción de microcápsulas, divididos en tres grupos: procesos físicos, procesos químicos y procesos físico-químicos. En el presente trabajo se ensayaron distintas metodologías para la producción de microesferas y microcápsulas de quitosano. Según la metodología empleada se obtuvieron distintos tipos de esferas en lo que respecta a tamaño y densidad principalmente. Las micropartículas obtenidas se evaluaron mediante microscopía óptica, electrónica de barrido, así como se realizó la evaluación de su estabilidad y liberación del agente encapsulado. AbstractThe microencapsulation process of agents with biological activity (such as DNA, pharmaceuticals, proteins, probiotics, enzymes, etc.), from the technological view, could be defined as the coating process of those agents, under a molecular form, solid particles, or liquid globules, with materials of different nature, that gives particles particles of micrometric size. One of the most used natural polymers for the production of microspheres is chitosan (?-1,4-glucosamine). Various methods have been proposed for the production of microcapsules, divided into three groups: physical processes, chemical processes, and physico-chemical processes. In this work, it were assayed different methodologies for the production of chitosan microspheres and microcapsules. Depending on the methodology used, were obtained differente types of spheres in reference to size and density. The microparticles produced were evaluated with optic microscopy, scanning electronic microscopy, so as were evaluated its stability and liberation of the encapsulated agent.

We isolated and characterized three strains of Penicillium; P. citrinum, P. chrysogenum and P. variabile from acidic mediums with kraft liquor as carbon’s source. We analyze their capacity to modify polyphenols. Preliminary assays confirmed the capabilities of these microorganisms to modify and degrade polyphenolic compounds like lignin. We demonstrate that they can grow in mediums with phenolic models and metoxilated compounds such as 3,4,5-trimetoxy benzaldehyde, syringic acid, resorcialdehyde, guaiacol and coniferyl alcohol, so they have the enzymes for oxidative, depolimerizating and demetoxilated reactions. The identification and characterization of these enzymes was made trough bioinformatics studies which allow us to relate different metabolic routes and enzymes from different genus and species. We also study the metabolism of Trichoderma reesei, isolated from Costa Rica’s mediums in order to use it as a consortium to modify polysaccharides. We believe that Penicillium’s consortium could modificate lignocelulosics in pretratement’s process for biofuel’s production or for chemist’s obtaining as modified phenols and their resins. We think that they reduce poliphenolic industrial residues. The use of this new efficient consortium of Deuteromycetes led us to innovate in traditional process for obtaining modificated phenols., Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 1494-1497

The microencapsulation process of agents with biological activity such as, DNA, pharmaceuticals, proteins, probiotics and enzymes could be defined, from the technological point of view, as the coating process of those agents, under a molecular form, as solid particles, or as liquid globules, with materials of different nature, that gives particles of micrometric size. One of the most used natural polymers for the production of microspheres is chitosan (β-1,4-glucosamine). This polycationic biopolymer, is the chitin soluble form (deacetylated form), a linear polymer constituted by N-acetylglucosamine residues, obtained from the exoskeleton of crustaceans, for example from shrimps. In this work, different methodologies have been assayed for the production of chitosan microspheres and microcapsules. The morphology of the produced microcapsules was evaluated by optical and scanning electron microscopy. Stability and liberation studies of the encapsulated agent have been also performed. Concerning the membranes, it was evaluated the production of chitosan and chitosan-collagen membranes. Both types were also analysed by SEM.