Publications by authors named "Steinerova N"

Ergot alkaloid enantiomer derivatives were resolved using capillary zone electrophoresis. The effect of cyclodextrins, added to the background electrolyte, on the migration time and the resolution was studied. Good separation for epimeric ergot alkaloid derivatives was also obtained using phosphate buffer at pH 2.

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Mycelium of Streptomyces cinnamonensis mutant strains cultivated in a synthetic medium with glycine produced protoplasts after lysis of cell walls with lysozyme. The protoplast yield was up to 95%. The protoplasts could revert and mycelial forms were thus regenerated.

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The GC-MS method was used to analyze fatty acids in a parent strain of Streptomyces lasaliensis and its two mutants producing only lasalocid or quinomycin. The biosynthesis of these substances bears relation to differences in the relative proportion of fatty acids. Biosynthetic relationships were revealed between the starter fatty acid units, their precursors, i.

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In addition to lasalocid, an oligoether coccidiostatic compound, other compounds are synthesized by Streptomyces lasaliensis. Mutants producing either of two antibiotics, lasalocid A or quinomycin A (an antibiotic of quinoxaline character), were obtained by natural selection and by mutagenesis. Methods of isolation, purification and estimation of both compounds were established.

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Streptomyces aureofaciens glucosidizes 1,2,4-trihydroxy-9,10-anthraquinone (purpurin) added to the cultivation medium to yield the corresponding 2-beta-D-glucoside. The identity of the glucoside was demonstrated by comparing its physico-chemical properties with data of an authentic sample prepared synthetically. A further chemical glucosidation of the acetylated 2-beta-D-glucoside gives rise to 2-(hepta-O-acetyl-beta-gentiobiosyl)-4-(tetra-O-acetyl-beta-D-gluc opyranosyl) purpurin.

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The immunostimulatory and immunoinhibitory effects of 44 hydroxyanthra- and hydroxynaphthoquinone derivatives in tissue culture were investigated. In the test system used, the final effect, i.e.

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Differential centrifugation, precipitation with ammonium sulphate and chromatography on DEAE-cellulose led to a twenty-fold purification of glucosyltransferase from Streptomyces aureofaciens B 96. The Michaelis constants for glucosyluridyl diphosphate (UDP-glucose) was 10.8 microM for 1,2-dihydroxy-9,10-anthraquinone (alizarin) 110 microM; the maximum rate of glucosylation reaction was 5.

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A total of 40 substances were tested for their inhibitory effect on the multiplication of a bacteriophage in a growing culture of Bacillus licheniformis and their influence on bacitracin production. Acriflavine was the only substance which, at a concentration of 3 microgram ml-1, completely suppressed phage multiplication while having no effect on the growth of Bacillus licheniformis and on the production of the antibiotic.

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Streptomyces aureofaciens B 96 grown on a synthetic medium glucosylated exogenous 1,2-dihydroxy-9,10-anthraquinone (alizarin). The glucosylation was inhibited by 2,4-dinitrophenol added to the cultivation medium. A cell-free preparation was obtained from the mycelium isolated after 16 h of growth and was found to catalyze the transfer of glucose from glucosyluridyl diphosphate to 1,2-dihydroxy-9,10-anthraquinone, giving rise to 1-hydroxy-2-(beta-D-glucopyranosyloxy)-9,10-anthraquinone.

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Both isomeric monohydroxyanthraquinones (1a, b), three dihydroxyanthraquinones (alizarin 1c, chrysazin 1d, and anthraflavin 1e) and corresponding acetylated (2) and free (3) beta-D-glucosides were screened for antitumour and immunosuppressive activity. Furthermore, four O-acetyl and O-benzyl derivatives of alizarin (5a--d) were tested. Antitumour activity was judged by the inhibition of growth of syngeneic tumours in the treated recipients and immunosuppressive activity by the effect on tumour growth or on skin graft survival in pretreated allogeneic recipients; as standard of reference served the activity of certain cancerostatic or immunosuppressive drugs used in clinical practice.

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Five mono- and dihydroxyanthraquinones as well as 12 of their glucosides (both free and acetylated) were tested with six different microbial species using the plate-diffusion method. None of the tested substances was active against Escherichia coli, 15 of the 17 substances displayed an activity toward Bacillus subtilis, Bacillus cereus, Candida albicans, Saccharomyces cerevisiae and Streptomyces aureofaciens. Relationships between the substance type and biological activity are discussed.

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