Evaluation of ozone pretreatment influence in the saccharification of sugarcane bagasse by the enzymatic extract produced by a newly isolated thermophilic fungus

• Grant number: 12/20403-0
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: January 10, 2013
• End date: July 09, 2013
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Daniela Alonso Bocchini
• Grantee: Josiani de Cassia Pereira
• Supervisor: Silvia Bolado Rodríguez
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Institution abroad: Universidad de Valladolid (UVa), Spain
• Associated to the scholarship: 11/12794-6 - Isolation and selection of thermophilic/thermotolerant filamentous fungi producer of cellulases and xylanases and application of the enzymatic extracts in sugarcane bagasse saccharification, BP.MS

Abstract

Microbial cellulases are enzymes that have potential for application in many biotechnological processes, especially in the enzymatic saccharification of sugarcane bagasse to obtain second generation ethanol. Filamentous fungi are microorganisms that stand out in the production of these enzymes, especially by solid state fermentation (SSF), an advantageous process due to the availability and low cost of the substrates, as well as the high yields obtained . The thermophilic fungi are of special interest in this context, since they are better adapted to a possible increases in temperature during the SSF, especially in large scale. Furthermore, they generally produce enzymes more active and stable at high temperatures, desirable characteristics for various biotechnological and/or industrial applications, including saccharification of lignocellulosic materials such as sugarcane bagasse. Due to bagasse recalcitrance, chemical, physical and/or biological pretreatments have been proposed in order to facilitate the access of cellulases to their substrates and to obtain higher yields in enzymatic saccharification. This project proposes the use of ozone as a pretreatment of sugarcane bagasse and the saccharification of pretreated and in natura bagasse by the enzyme extract from the thermophilic fungal isolate named JCP 1-4. This fungus was selected among the 26 isolates obtained by the candidate while developing your Master Project, since it is a good producer of cellulolytic enzymes, and it will be identified in the coming months, with previously established partnership with Prof. Dr. André Rodrigues, Department of Biochemistry and Microbiology - IB/UNESP, Rio Claro. The experiments concerning to this proposal will be performed at the Grupo de Tecnología en Procesos Químicos y Bioquímicos, Departamento de Ingeniería Química y Tecnología del Medio Ambiente of the Universidad de Valladolid - Spain, under the guidance of Silvia Bolado. This research group has obtained very promising results with the cited pretreatment technology followed by saccharification with commercial cellulases, working with wheat straw, barley and sugarcane bagasse, and has interest in exploring the use of enzymes derived from fungi recently isolated, as a way to cheapen the process and comparing yields. Pretreated and in nature bagasse will be chemically characterized (cellulose, hemicellulose, lignin - acid soluble lignin and acid insoluble lignin), in order to evaluate the effectiveness of pretreatment, relate chemical compositional changes to saccharification yeld, evaluate the possible attack of the pretreatment to carbohydrates and evaluate the formation of fermentation inhibitors in the hydrolysate. (AU)