| Abstract [eng] |
We investigated and compared relation between cellulolytic and chitinolytic micromicetes from two soils (humus and less humus soil). Also selected strains of micromicetes with enzymatic activity from media with various polisacharides. The biggest attention was turned to cellulose and cellulolytic micromicetes, but for comparison we investigated also anthropogenic substrates – paper remake waste and different phases of this process and relation between enzymatic activity of micromicetes.The research was made with stages, picking active strains on selective media with cellulolytic and chitinolytic activities and making detailed assay according to quantitative aspect. Established different abundance of micromicetes in two soils (accordingly 6,4 thousand and 80 thousand CFU/g dry soil). There was different percentage of micromicetes utilizing cellulose or chitin and it depended on every soil micromicete activity and community structure. Complexes of micromicetes from soil differ from that of anthropogenic substrates, but some of them were the same and their cellulolytic activity was patent. We selected 1550 strains of micromicetes, 27 species. Cellulolytic activity was different not only between different strains, but in one strain line it were observed some differences too (ex. Trichoderma strains). The biggest cellulolytic activity by this research was observed in these strains: Aspergillus, Chaetomium, Clonostachys < Gliocaldium, Myrothecium, Penicillium ir Trichoderma. Looking at quantitative endoglucanase and paper cellulase analysis results, the most active were Penicilium funiculosum (active strains 27.1%), P. simplicissimum (15.7%), Stachybotrys chartarum (7.5%) and Aspergillus repens (4.7%) micromicetes. Gliomastix murorum var. murorum and Stachybotrys chartarum were selected from anthropogenic substrates, others – selected from soil. Relative chitinolytic activity observed in strain Trichoderma, almost all Paecilimyces and Arthrobotrys strains. The most active by endoglucanase activity micromicetes were Metarhizium and Beuaveria species. Cellulases are important not only degrading cellulose in soil, but to plant pathogens, penetrating to plant cells at invasion time. The endoglucanase activity of these micromicetes was similar to those growing in media with colloid chitin, which directly stimulated chitinase synthesis. Antagonists showed better chitinolytic activity in media with Botrytis cinerea, Fusarium culmorum and F. oxysporum cell walls and the activity of all antagonists in media with glucose was lesser than in media with pathogenic cell walls. These strains can be used as bioagents against pathogenic micromicetes. In mixed micromicete culture research showed that antagonistic activity depends on development on substrate, on type of polisacharide. This depended on carbon source in media. There were different activities of endoglucanase in separate and mixed cultures of micromicetes in media. The acidity was different too. The biggest difference of acidity was in separate and mixed cultures with Trichoderma and Aspergillus niger. The endoglucanase activity of both micromicetes was big in separate cultures and decreased noticeably in mixed cultures. To find the combination of cultures for the aim to increase the concentrations of egzoenzymes it is important to choose optimal conditions (pH and temperature), but it is difficult to match them in mixed cultures. Chosen strains of micromicetes can be potential producers of cellulases and chitinases, but it is needed detailed analysis of every chosen enzyme for creating characteristic of general enzymatic system and their components. |
