Š. Kučár

Immobilisation of β-d-galactosidase from Escherichia coli on cellulose beads and its use for the synthesis of disaccharide derivatives

beta-D-Galactosidase, isolated from cloned E. coli, was immobilised on cellulose beads via oxidation with sodium periodate, activation by cyanuric chloride, or diazotisation. beta-D-Galactosidase immobilised via azo bonds showed the highest relative activity and thermostability, and was used for synthesis of disaccharide methyl glycosides.

Antibacterial effect of some phenylhydrazones.

In earlier work we demonstrated an inhibitory effect of sugar hydrazones on bacterial growth most powerful being peracetylated D-erythrose and D-galactose derivatives (Zemek and Linek, 1977). The present paper is concerned with the effect of subst i tut ion by a nitro group in phenylhydrazones of D-galactose and the effect of hydroxyl group removal from the aldose moiety of 2,4-dinitrophenylhydrazone on the antibacterial action of these compounds. The antibacterial effect was also investigated in some nonsugar 2,4-dinitrophenylhydrazones. The antibacterial effects of individual phenylhydrazones were studied as shown earlier (Zemek and Linek, 1977). The substances were used in the form of dimethyl sulphoxide solutions, the final concentration of the solvent in the cultivation medium being maintained at 1 ~ The carbonyl compounds were commercially available, mostly from Koch-Light; D-mannose deoxy derivatives were prepared according to KuSs et al. (in press), 3-deoxy-n-r ibo-hexose was prepared according to Ku5Ar et al. (1975). Phenylhydrazones were prepared according to Lloyd and Doher ty (1952), acetylated derivatives according to Kovs et al. (1974). The results of anbibacterial act ivi ty assays are summarized in Tables I I I I . As seen from Table I, the antibacterial effect of all phenylhydrazine derivatives under s tudy was increased with the formation of the corresponding D-galactose hydrazones. The effect of subst i tut ion by a nitro groups on the aromatic ring is perceptible in particular with sugar 2,4-dinitrophenylhydrazones; 2-nitrophenyland 4-nitrophenylhydrazones exhibit a lower effect. The antibacterial ac t iv i ty of D-glucose and D-mannose monodeoxy derivatives is higher in the case of peracetylated hydrazone derivatives as compared with the

Antimicrobial effect of sugar osazones and anhydro sugars

The antimicrobial effect of 14 sugar osazones and anhydro sugars was studied with model strains ofMicrococcus luteus, Bacillus licheniformis, Escherichia coli and strainsStaphylococcus aureus andPseudomonas aeruginosa isolated from clinical material. The relationship between the structure of these compounds, their solubility in water and 1-octanol and antimicrobial effect was investigated.

Antimicrobial effects of sugar osazones

Antimicrobial effects onMicrococcus luteus, Bacillus licheniformis andEscherichia coli were determined using a group of sixteen aldose osazones.

2-Deoxy-d-lyxo-hexonic Acid from 2-Deoxy-d-lyxo-hexose byPseudomonas aeruginosa Fermentation

Aerobic fermentation of media or solutions containing 2-deoxy-@#@d-lyxo- hexose and calcium carbonate by bacterial cells capable of oxidizing aldoses to aldonic acids was used to prepare 2-deoxy-d-- lyxo- hexonic acid; the acid was isolated in a 62 % yield in the form of its 1,4-lactone.

Biochemical dehydrogenations of saccharides. VII. 2-Deoxy-D-gluconic acid from 2-deoxy-D-glucose.

Fermentation of a medium containing 5% 2-deoxy-D-glucose and barium carbonate by a strain ofPseudomonas aeruginosa yielded barium 2-deoxy-d-gluconate. The yield was 77% theoretical. The strain in question makes it possible to prepare directly calcium, magnesium, manganese and ferrous salts of 2-deoxy-d-glueonic acid. A treatment of 6% solution of 2-deoxy-d-glucose with commercial glucose oxidase preparation caused also a complete dehydrogenation.