Implementación de una línea de evaluación para subproductos agroindustriales como sustrato para la producción de bioetanol. Presacarificación-sacarificación/fermentación simultánea

Abstract

The study of alternative routes with better efficiency and low costs is the focus of study in Bioethanol nowadays. For this reason, in this paper we use two kind of filamentous fungi; Trichoderma harzianum and Pleurotus ostreatus, cultivating them in different kind of residual sustrates; as grape pomace, sawdast and sunflower cake provided by national industries, to establish an evaluation system for the the alcohol production process by lignocellulitic microorganisms. In this study, we contemplate three assays; a Presaccharification assay to reduce the saccharification time by predigesting the substrates; an enzymatic saccharification assay using the cellulases produced by the semi solid fermentation of the presaccharification process, and a fermentation assay which involved a thermostable microorganism; Kluyveromyces marxianus (NRRL Y-665) for a simultaneous Saccharification and Fermentation assay. From the results we could conclude that the system used is suitable for the production of reducing sugars and alcohol. Comparative studies using different substrates demonstrate that there is a great use of reducing sugars when the matrix is grape pomace or sunflower cake, roughly a 50%. The subproducts  from presaccharification can affect the microorganisms and act as inhibitors of the process, which makes critical the study of this degradation products and how to reduce them . Finally, we can conclude that this system is effective for biomass storage in a stable way and in the same presaccharification process.