CELLULASE ACTIVITY OF MYCELIAL FUNGI COLLECTION STRAINS STUDY

Relevance. Cellulases occupy the third place in the world among industrially produced enzymes. This is largely due to the fact that cellulose is the main component of plant material, and the lignin-cellulose part of biomass accumulates in huge quantities in the form of waste from agriculture, woodworking and other industries. To convert this material, it is necessary to perform its enzymatic cleavage to glucose and cellobiose using various cellulases. The purpose of this work was to study the cellulose activity of collection strains of mycelial fungi for the selection of promising strains-producers of cellulases Material and methods. The objects of the study were 13 strains of 12 species of micromycetes from the microorganisms biocollection of the VILAR, belonging to the genera Aspergillus, Monilia, Penicillium. The work used surface and deep cultivation of fungi on media with partial replacement of sucrose with cellulose. The cellulolytic activity of microorganisms was assessed by the growth rate of colonies. In addition, at the last stage of cultivation, the surface of the agar was stained with Lugol solution, the diameter of the lysis zones was measured and lysis indices were calculated. Mushroom cultivation in deep conditions was carried out in flasks on a shaker. The seed material was a suspension of spores of seven-day deuteromycete cultures. In the culture fluid filtrates, the total cellulase activity was evaluated by determining reducing sugars, as well as the concentration of sucrose. Statistical processing of the results, regression and correlation analysis were carried out on a personal computer using the Microsoft Office Excel 2010 statistical software package. Results. During surface cultivation on a modified medium with cellulose, fungi formed colonies and well-defined lysis zones, which indicated the synthesis and secretion of cellulolytic enzymes. Differences in radial growth rates and lysis indices were found in individual species and strains of micromycetes. Using regression and correlation analysis, six strains were selected for deep cultivation. The presence of hydrolytic activity with respect to microcrystalline cellulose in the culture fluid of fungi during cultivation on a medium with partial replacement of sucrose with cellulose is shown. Conclusions. The synthesis of cellulases was found by the studied fungal cultures during surface and deep cultivation. A comprehensive analysis of the data obtained makes it possible to select the most promising cellulase-producing strains.