Holocellulase from filamentous fungi prospected from the Brazilian Cerrado biome

Cerrado is a Brazilian biome that consists of different vegetation types, where can be prospected microorganisms with potential to generate products of high-added values for various industrial sectors, such as plant cell wall-degrading enzymes from filamentous fungi. This study evaluated the potential for production of holocellulases from filamentous fungi isolated from decaying wood found in Cerrado. Fungal isolates were screened for holocellulases production and an enzymatic index was used. Enzyme-producing fungi were selected out of 110 isolates (60.9%) and eight strains with the highest enzymatic indexes were cultured in submerged fermentation containing carbon sources, such as elephant grass, sugarcane bagasse and okara (soy milk processing residue). Holocellulases assays (FPase, endoglucanase, exoglucanase, xylanase, mannanase and pectinase) were conducted with filtered (Whatman n˚1) crude enzyme extracts. The isolates MD-05 and AR-113 cultured on elephant grass exhibited FPase activities of 0.579 and 0.368 UI.mL^-1, respectively. Interestingly, a red pigment was produced in the media colonized by the isolate AR-113, especially in the presence of okara. Ongoing studies are been conducted (crude extracts) for enzymatic hydrolysis of elephant grass and sugarcane bagasse previously pre-treated by the white-rot fungi Pleurotus ostreatus and Ganoderma lucidum. Also, the cultivation of the isolated AR-113 (okara) is being optimized bioreactor, in that the crude extract is going through a process of separation of pigments (red) of the enzymes of interest (cellulases). The results indicated that aqueous two-phase micellar system (ATPMS) was able to separate visible pigments and possible cellulases present in fermented broth, that partitioned in the bottom phase.