EXTRACELLULAR PROTEINS SECRETED BY TRICHODERMA HARZIANUM PRODUCED BY FERMENTATION OF SOLID-STATE SUGARCANE BAGASSE AS CARBON SOURCE

Ana Carolline Ribeiro de Toledo Pinto (UnB); Pedro Alves Martins (UnB); Diana Paola Gómez Mendoza (UnB); Marcelo Valle de Sousa (UnB); Edivaldo Ximenes Ferreira Filho (UnB); Carlos André Ornelas Ricart (UnB)

Trichoderma is a fungi genre widely studied because of its great capacity of synthesizing and secrete numerous enzymes. Trichoderma harzianum is one of the most common species among this group, being found on several substrates as vegetal decomposing material. This work aimed at analyzing the extracellular proteins secreted by T. harzianum during fermentation of solid-state sugarcane bagasse as carbon source. In order to obtain T. harzianum spores, the fungus was grown on Petri dishes containing synthetic medium supplemented with 1% sugarcane bagasse as carbon source. After ten days, the spores were collected with a 0,9% NaCl solution and this spore suspension (1x10⁸ ml^-1) was used to inoculate six erlenmeyers containing 5g of sugarcane bagasse dampened with 30mL of synthetic medium. The culture was then maintained at room temperature for 0, 3, 6, 9, 12 and 30 days. The experiment was made on triplicate. After growth procedure, the crude extract was washed with 50 ml of sodium acetate buffer (100mM; pH 5,0) during 30 minutes under agitation, followed by vaccum filtration. In order to take off the remaining spores, the obtained supernatants were then centrifuged at 6000rpm/15min. The obtained enzyme extract are now being subjected to enzymatic assays to determine activities of cellulases (CMCases and FPases), hemicellulases (xylanases), mananases and pectinases. The protein profile of the samples are also being analyzed using electrophoresis techniques such as SDS-PAGE and 2D-PAGE. This work wants to analyze the capacity of Trichoderma harzianum to degrate sugarcane bagasse as carbon source, and the different types of enzymes secreted to degrate the different kinds of cellulosis and hemicellulosis structures. We expect as results identifying the differential protein profiles resulted for each day of culture, and try to answer the reasons of such variable profiles, by characterization of each protein (or as much as possible) in SDS-PAGE electrophoresis (one and two dimensions).