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Carbohydrate Research | 1968

Mass spectrometry of uronic acid derivatives

Vladimír Kováčik; Š. Bauer; Jozef Rosík; P. Kováč

Electron impact mass spectra of a series of aldobiouronic and pseudoaldobiouronic acid per-0-methyl derivatives and of the corresponding 4,5-unsaturated analogues, found normally among the products of methylation of uronic acid containing disaccharides as a result of methylation accompanying &elimination, have been studied. Using labelling experiments, metastable transition measurements and high resolution mass spectrometry, the fragmentation mechanisms of substances of this class have been deduced. Application of the information to the structure elucidation of this type of compound is discussed. It is concluded that from the mass spectra alone it is possible to determine the molecular weight, the cycle masses as well as the mode of linkage between the monomeric units. The appearance potentials of ions formed by cleavage of the glycosidic linkages have also been determined and the energetic differences encountered in the fission of the glycosidic linkages of various types of uronic acid containing oligosaccharides are discussed.


Carbohydrate Research | 1983

Polysaccharides from the roots of the marsh mallow (Althaea officinalis L.): Structure of an arabinan

Peter Capek; Rudolf Toman; Alžbeta Kardošová; Jozef Rosík

Abstract A water-soluble l -arabinan isolated from the mucous material of the roots of the marsh mallow ( Althaea officinalis L.) has a highly branched structure of ∼90 α- l -arabinofuranosyl residues variously linked by (1→5), (1→3), and (1→2) bonds. Some of the l -arabinosyl groups are involved in branches through O-2, O-3, and O-5. There was good agreement between the results obtained by chemical and 13 C-n.m.r.-spectroscopic methods. The polymer has essentially the same structural features as those found for l -arabinans isolated from other plant sources.


Carbohydrate Research | 1968

Mass spectrometry of uronic acid derivatives Part IV. The fragmentation of methyl ester methyl glycosides of methylated aldotriouronic acids

Vladimír Kováčik; Š. Bauer; Jozef Rosík

Abstract The mass spectra of methyl ester methyl glycosides of methylated uronic acids, methyl ester methyl glycosides of methylated aldobiouronic acids of different types, and of methyl ester methyl glycosides of acetylated aldobiouronic acids having 4- O -methyl- d -glucuronic acid as the acidic component were obtained. Fragmentation patterns of these compounds, characteristic features of their mass spectra, and their importance for analytical applications are discussed.


Folia Microbiologica | 1978

Enzyme preparations fromAspergillus flavus for structural studies of the peach gum polysaccharide

Alžbeta Kardošová; Jozef Rosík; Jozef Kubala

Extra- and intracellular glycanohydrolases were isolated fromAspergillus flavus and partially characterized. Both preparations exhibited β-galactosidase activity. Gel chromatography of the extracellular enzyme preparation on Sephadex revealed one protein fraction containing β-galactosidase activity and a second one exhibiting mainly β-xylosidase activity. Electrophoresis in starch gel and disc electrophoresis in polyacrylamide gel showed that the preparation obtained from the cultivation broth contained five protein fractions, whereas two protein fractions could be detected in the intracellular preparation. Hydrolysis of a partially degraded polysaccharide of peach gum by the above preparations yieldedd-galactose as the main product and traces ofd-mannose,l-arabinose,d-xylose and a number of oligosaccharides.


Phytochemistry | 1975

Utilization of degraded peach gum polysaccharide by Aspergillus flavus

Alžbeta Kardošová; Jozef Rosík; Jozef Kubala

Abstract d -Galactose, d -mannose, d -xylose, l -arabinose, and d -glucuronic acid and its γ-lactone were examined as carbon sources for the culture of Aspergillus flavus . d -Mannose was taken up the most rapidly and d -glucuronic acid and its γ-lactone the least rapidly. A partially degraded polysaccharide from peach tree gum ( Prunus persica [ L. ] Batsch containing the above sugars together with d -glucuronic acid and its 4- O -methyl ether was used as substrate for another A. flavus culture. It was found that d -galactose was the major sugar passing into the culture medium with lower proportions of d -xylose, l -arabinose, 2- O -β- d -glucopyranuronosyl- d -mannose, and 6- O -β- d -glucopyranuronosyl- d -galactose. This indicates that the fungus produces extracellular exo- and endo-glycanohydrolases which may be useful in structural studies on polysaccharides.


Carbohydrate Research | 1971

Infrared spectroscopy of peach-gum polysaccharides of Prunus persica (L.) Batsch

Jozef Rosík; Alžbeta Kardošová; Jozef Kubala


Carbohydrate Research | 1982

Selective monobenzylation of methyl α-l-rhamnopyranoside and its 4-benzylether in the presence of tin(II) chloride

Rudolf Toman; Jozef Rosík; Miroslav Zikmund


Collection of Czechoslovak Chemical Communications | 1984

Polysaccharides from the roots of Althaea officinalis L.: Structural features of D-glucans

Peter Capek; Rudolf Toman; Jozef Rosík; Alžbeta Kardošová; František Janeček


Carbohydrate Research | 1988

Polysaccharides from the roots of the marsh mallow (Althaea officinalis L., var. Rhobusta): dianhydrides of oligosaccharides of the aldose type

Peter Capek; Dušan Uhrín; Jozef Rosík; Alžbeta Kardošová; Rudolf Toman; Vincent Mihálov


Collection of Czechoslovak Chemical Communications | 1966

The structural features of cherry-tree gum ( Prunus avium L. var. juliana L.)

Jozef Rosík; V. Zitko; Š. Bauer; J. Kubala

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Peter Capek

Institute of Chemistry

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Rudolf Kohn

Institute of Chemistry

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Š. Bauer

Institute of Chemistry

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Miroslav Zikmund

Slovak Academy of Sciences

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