Non-conventional yeast have great potential for use in biotechnology because of their phenotypic diversity, especially if they are able to grow on a lignocellulosic substrat, which is economically and environmentally interesting solution for production of chemicals. In our research, we selected 68 genetically diverse strains of genus Dekkera, which were typed using RAPD-PCR method and tested for their ability to grow on components of lignocellulosic hydrolysate. For screening test 12 yeast strains isolated from plant sources and 2 typical strains were added. Second screening test included testing of strain growth on various types of lignocellulosic hydrolysates. We chose 28 strains based on growth rate assessment, to which we added 28 new strains. Strains were grouped according to their relative growth rate. Seven strains were aerobically cultivated for which specific growth rate and percentage of carbohydrate consumtion in hydrolysate medium were evaluated. Specific growth rate was deterimed by plating at the beginning and at the end of cultivation, sugar concentrations were mesasured by high performance liquid chromatography in spent media. The most suitable strains for the efficient use of lignocellulosic hydrolysate were Schwanniomyces polymorphus ZIM 2980, which utilized 97,0% of sugars in medium, Pichia kudriavzevii ZIM 3106, which utilized 82,4% of sugars in medium and Saccharomyce cerevisiae ZIM 3418, which utilized 83,1% of sugars in medium. We found out that only some strains/species of non-conventional yeast are able to use lignocellulosic hydrolysate, which indicates a relatively large variety of yeast that can be linked to source of yeast's isolation.
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