Janusz Szczodrak

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Among 47 tested yeast strains, belonging to different genera, only two cultures of Kluyveromyces fragilis and Fabospora fragilis showed beta-galactosidase activity in shaken flasks. Three types of extraction were used to release the enzyme from K. fragilis cells: solvent and detergent extraction, freezing and thawing extraction, and mechanical(More)
The strain Streptococcus sobrinus CCUG 21020 was found to produce water-insoluble and adhesive mutan. The factors influencing both stages of the mutan production, i.e. streptococcal cultures and glucan synthesis in post-culture supernatants were standardized. The application of optimized process parameters for mutan production on a larger scale made it(More)
Of the three cariogenic streptococci grown in four various culture media, the strain Streptococcus mutans 20,381 was found to produce large amounts of extracellular glucosyltransferase and water-insoluble, adhesive exopolysaccharide when grown in batch culture on brain-heart infusion broth. Methylation and nuclear magnetic resonance analyses revealed that(More)
Autohydrolysis and ethanol-alkali pulping were used as pretreatment methods of wheat straw for its subsequent saccharification by Trichoderma reesei cellulase. The basic hydrolysis parameters, i.e., reaction time, pH, temperature, and enzyme and substrate concentration, were optimized to maximize sugar yields from ethanol-alkali modified straw. Thus, a 93%(More)
Two strains of A. niger were cultivated on beet molasses medium by the surface method, and the effects of iron on the mycelium formation, the rate of sugar utilization, the activity of aconitate hydratase, and synthesis of citric acid were determined. Among various sources of di- and trivalent iron, ferrous sulphate was chosen for studies, which most(More)
A total of 58 yeast strains from 12 genera were assayed for their ability to grow and ferment carbohydrates in standard Durham tube test at 40, 43, and 46 degrees C. Based on the kinetic parameters for glucose fermentation in shaken flask cultures, the strain Fabospora fragilis CCY51-1-1 was chosen for further studies. It reached about 56.0 and 35.0 g(More)
The chemical structure of a water insoluble α-glucan isolated from the cell wall of Aspergillus wentii was described on the basis of total acid hydrolysis, methylation analysis, and 1D and 2D NMR studies (TOCSY, DQF-COSY, NOESY and HSQC) as well as other instrumental techniques. It was established that the analyzed preparation contained a linear polymer(More)
The agaric basidiomycete Nematoloma frowardii has been suggested as a good alternative for production of the extracellular ligninolytic enzyme, manganese-dependent peroxidase (MnP). Some cultural and environmental factors influencing the enzymatic activity in shaken flasks and aerated fermenter cultures were evaluated to improve the yields of the process. A(More)
  • J. Szczodrak
  • European journal of applied microbiology and…
  • 2004
The activities of ACH1, NAD-ICDH, NADP-ICDH and CS were determined in cell extracts of high and low citric acid-producing strains of A. niger, cultivated on molasses medium by the surface or submerged method. A high differentiation in the activities of the enzymes studied was found to occur at various accumulation stages of citric acid and during its(More)
Two hundred and fifteen fungal strains were screened for extracellular dextranase production with a diffusion plate method. The best enzymatic activity (12–19 DU ml−1) was achieved byPenicillium notatum 1, a species for which the dextranase productivity has not yet been published. Some of the parameters affecting enzyme production have been standardized.(More)