Currently, most of the world's energy needs are met by fossil fuel resources. Several different technologies can be used to transition to more sustainable energy sources. Cellulose is the most abundant organic material in the biosphere. Therefore, the isolation and industrial use of cellulases could be used in the production of biofuels from organic cellulose sources.
Trichoderma reesei is a mesophilic, filamentous fungus, known for its efficient production of cellulase enzymes, which are necessary for breaking down crystalline cellulose into glucose. In 1950 it was isolated in the Solomon Islands from decaying textiles. T. reesei produces three main types of cellulolytic enzymes: endogluconase, cellobiohydrolase, and b-glucosidase. Endogluconase shears internal connections in cellulose, cellobiohydrolase cleaves cellobiosyl units from the non-reducing end of cellulose, and beta-glucosidase cleaves glycosyl units from the non-reducing end of cellulose oligosaccharides. These enzymes work synergistically to depolymerize cellulose and convert it into glucose [1]. However, the close relationship between lignin and cellulosic biomass can create barriers to the enzymatic hydrolysis of cellulose into fermentable sugars. Hemicellulose and lignin prevent cellulosic enzymes from functioning, inhibiting enzyme structure and reducing matrix pore size. The crystalline structure of cellulose with a glucan chain stops the hydrolysis process. Different pretreatment methods have specific effects on different lignocellulosic components. However, a significant number of them can create some kind of obstacles to the action of cellulases [2].
In our study we used RTS-1C bioreactor for cultivation of T. reesei ATCC 26921 cells. When growing T. reesei preculture in the bioreactor, it was important to create a constant aeration, to maintain optimal pH and to ensure the optimum temperature. After ensuring the optimal preculture growth conditions, the developed methodology was applied to the cultivation of cellulase-producing cultures. In the further cultivation of enzyme-producing cultures, it is planned to study the influence of the processing of cellulose raw materials on the final yield of enzymes, also to investigate different additives that can increase the excreted amount of the enzyme or the increase enzyme activity. It is expected to optimize the cultivation, enzyme production and purification technologies to provide convenient, cost-effective, and efficient conditions, as well as to investigate the specificities of the culturing of the culture in the bioreactor.