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Chromatographic fractionation and analysis of the main components of eggplant (Solanum melongena L.) leaf cuticular waxes

Haliński Ł. P., Szafranek J., Szafranek B. M., Gołębiowski M., Stepnowski P.

Acta Chromatographica

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2009

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Vol. 21, no. 1

127-137

EN

The composition of eggplant ( Solanum melongena L.) leaf cuticular waxes was investigated. Chemical composition was determined as the first step in recognizing the importance to insect pest resistance of eggplant leaf surface chemistry. Waxes were extracted by dipping leaves into dichloromethane for 40 s. Relatively large samples were then fractionated by 'flash chromatography' on silica gel. Compounds were identified on the basis of their mass spectra from GC-MS analysis and retention data from GC-FID analysis, and quantified on the basis of peak areas from GC-FID analysis. Straight-chain alkanes and methyl-branched alkanes were the most abundant wax components. Minor quantities of esters of fatty acids with triterpene and aliphatic alcohols, free triterpene and aliphatic alcohols, sterols, and free fatty acids were also present on the eggplant leaf surface. This method is suitable for analysis of complex mixtures of plant cuticular lipids. It is also applicable to separation of samples for biological tests on insects.

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Chemical Structure of the Salmonella Anatum (O:3,10) O-antigen

Gajdus J., Kaczyński Z., Czerwicka M., Dziadziuszko H., Szafranek J.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 7

1393-1393

EN

An O-specific polysaccharide containing D-galactose, D-mannose and L-rhamnose was obtained by mild acid hydrolysis of the lipopolysaccharide of the Salmonella Anatum bacterium. The structure of the polymeric O-antigen was studied by composition analysis and by 1D and 2D, 1H and 13C NMR spectroscopy. The repeating unit of the polymer was identified as a linear trisaccharide with the structure shown below, in which the galactose residue was partially O-ac ety lat ed at C-6; this was re spon si ble for the mol e cule’s structural heterogeneity. → 3)-D-Galp-(1𔾺)-D-Manp-(1𔾸)-alfa-L-Rhap-(1→ 6 OAc (75%).

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Pierwszorzędowa struktura antygenów O bakterii rodzaju Salmonella

Gajdus J., Głośnicka R., Szafranek J.

Wiadomości Chemiczne

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2006

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[Z] 60, 9-10

621-653

EN

Salmonella spp. are pathogenic Gram-negative bacteria that belong to Enterobacteriaceae family with lipopolysaccharide (LPS) as a constituent of cell wall. This is an integral component of the outer membrane of the wall. Salmonella smooth (S) forms produce LPS, which is composed of three parts, chemically bonded together viz. polysaccharide O-antigen, oligosaccharide core region and lipid A. Antigens O (O-PS) together with H flagella antigens are the foundation of serological classification of these bacteria. O-chain, which is built with up to 50 oligosaccharide repeating units, is one of the products of mild acidic hydrolysis of LPS. Due to the fact that polysaccharide antigens are the sites of specific antibody complexing, any difference in primary and secondary structures of O-antigens reflect serological specificity of bacteria. Taking this fact into consideration, we can distinguish about 2541 Salmonella serotypes with O and H antigenic formulas defined [4]. In this review we present 55 chemical structures of O-antigenic repeating units of Salmonella strains including their heterogeneity structures. The structures can have 22 different monosaccharide residues usually in 3 to 6 sugar repeating units. We describe here selected chemical and spectroscopic (MS, NMR) methods for primary structure examination of these bacterial O-PS. Enzymatic and immunochemical methods are also described. Cross-reactions of Salmonella spp. with any other bacteria or blood group A, B, 0 antigens are explained on the molecular level. Thus, structural assignments of somatic antigens of Salmonella spp. allow us to understand the molecular level of the classification system of these bacteria.

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Repeating Unit Structure of Enterobacter sakazakii ZORB A 741 O-Polysaccharide

Szafranek J., Czerwicka M., Kumirska J., Paszkiewicz M., Łojkowska E.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 2

287-295

EN

The O-specific polysaccharide from Enterobacter sakazakii cell was isolated and structurally characterized. Lipopolysaccharide (LPS) was obtained from cell mass by hot phenol- water extraction procedure. Mild acid hydrolysis followed by gel filtration provided pure O-antigen (OPS). Two-stage sugar analysis detected tyvelose, rhamnose and galactose in the molar ratio of 1:1:2, and their linkages were established by means of methylation analysis. Sugar configurations, D or L, were determined by gas-liquid chromatography on an achiral liquid phase for (S)-(+)-2-butyl glycosides. D configuration was determined for galactose and 3,6-dideoxy-mannose (tyvelose), but L for rhamnose. Repeating unit structure was deduced by analysis of 1H and 13C NMR spectra. 1H and 13C NMR resonances have been assigned by homonuclear (COSY, TOCSY) and heteronuclear (HSQC, HMBC) correlations spectra. Anomeric configurations were determined from anomeric proton chemical shifts and 3JH1-H2 and JC-H coupling constants. Sugar sequences were established from comparisons of specific carbon chemical shifts with those in literature, two-dimensional nuclear Overhauser effect spectroscopy (NOESY), and heteronuclear multiple-bond correlation experiments (HMBC). The repeating unit structure of Enterobacter sakazakii was found to be as: alfa-Tyvp _2 _3)-alfa-L-Rhap-(1--3)-alfa-D-Galp-(1_3)-alfa-D-Galp-(1_ _6 O-Ac

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Structure of the Polysaccharide O-Antigen of Salmonella Aberdeen (O : 11)

Szafranek J., Kaczyńska M., Kaczyński Z., Gajdus J., Czerwicka M., Dziadziuszko H., Głośnicka R.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 9

1135-1140

EN

O-specific polysaccharide (OPS) of Salmonella Aberdeen was obtained from bacterial cell mass by water-phenol extraction procedure of lipopolysaccharide (LPS) followed by its mild acid hydrolysis and gel filtration of soluble carbohydrate material. Rhamnose, galactose, N-acetyl-glucosamine and mannose were detected and their linkages were established. Sugar configurations, D or L, were determined for (S)-(+)-2-butyl glycosides on an achiral capillary column. The structure of OPS was determined by analysis of spectra of 1H and 13C NMR and homonuclear and heteronuclear correlations spectra. Anomeric configurations were tentatively assigned by chromium trioxide oxidation and later proved by anomeric proton chemical shifts, H1-H2 coupling constants and proton coupled 13C spectra. Sugar sequences were established from comparisons of specific carbon shifts with those from literature, two-dimensional nuclear Overhauser effect spectroscopy (NOESY) and heteronuclear multiple-bond correlation experiments (HMBC). The repeating unit of S. Aberdeen OPS has the structure: _3)-_-D-GlcpNAc-(1_3)-[ _-D-Manp-(1_4)-]_-D-Galp-(1_4)-_-L-Rhap-(1_