Collagenolytic properties of micromycetes collection strains during long-term storage study

Relevance. The VILAR collection of micromycetes contains hydrolyzing collagen strains-potential producers of collagenases. When searching for enzymes producers, the stability of viability and biosynthetic activity of microorganisms is an important indicator. In this regard, the study of collagenolytic activity of mycelial fungi collection strains during long-term storage is relevant for solving applied and fundamental problems of modern biotechnology. Objective. Viability and collagenolytic activity of collection strains of micromycetes during long-term storage study. Material and methods. The object of the study were 16 micromycetesstrains, belonging to the genera Aspergillus, Beauveria, Paeci-lomyces, Penicillium, Phialophora. The cultures were stored under oil at 4 °C for 4 years. After storage, the viability and collagenase activity of microorganisms were evaluated during surface cultivation. In addition, deep cultivation of fungi was carried out with the determination ofcollagenolytic activity in the filtrates of the culture fluid. Results. Studies have shown that all micromycetes remained viable after 4 years of conservation under the selected conditions. During surface cultivation on a modified medium with the replacement of sucrose with collagen, fungi formed colonies and well-defined lysis zones, which indicated the synthesis and secretion of collagenolytic enzymes. Differences in growth rates and lysis indices were found for individual species and strains of micromycetes. Comparison of lysis indices before and after storage showed the stability of this indicator. Using regression and correlation analysis, five strains were selected for deep cultivation. Determination of collagenolytic activity in culture fluid filtrates confirmed the synthesis and secretion of collagenolytic enzymes by the studied micromycetes. Conclusions. Conservation of micromycetes on agarized Chapek media under oil at 4 °C ensures the preservation of viability and collagenolytic activity. The stability of the collagenolyticproperties of micromycetes during long-term storage was confirmed. For five strains selected on the basis of regression and correlation analysis, the secretion of collagenolytic enzymes into the culture medium during deep cultivation was shown.

micromycetes, collagen, collagenases, surface and deep cultivation