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1.
Plant Biol (Stuttg) ; 13(6): 932-9, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21973213

RESUMEN

The complex of species formed by eggplant (Solanum melongena L.) and its wild and weedy relatives (mainly S. incanum L. and S. insanum L.) is characterised by an extreme morphological divergence that is not always associated with genetic variation. The taxonomy of so-called 'spiny Solanum' species (subgenus Leptostemonum) is therefore extremely unclear. Cultivated eggplant lacks resistance to pests that frequently occur among the wild forms and species. As these wild plants are a potential gene pool for improvement of eggplant cultivars, knowledge of the characteristics of taxonomic relations between plants of different origin is crucial. We suggest using the leaf cuticular n-alkane chain length distribution pattern as an alternative taxonomic marker for eggplant and related species. The results are in good agreement with current knowledge of the systematics of these plants; at the same time, the method developed here is useful for verifying plant identification based on morphological traits. Analysis of 13 eggplant cultivars, five accessions of S. incanum and two lines of S. macrocarpon enabled the intraspecific variation within eggplant to be assessed as low. There was wide variability among S. incanum accessions, probably because plants described as S. incanum are members of a number of different species. Some Asian accessions (sometimes described as S. insanum) were found to be almost identical to S. melongena, while a truly wild African S. incanum plant showed extensive similarity. The usefulness of the chemotaxonomic approach in dealing with the S. melongena-S. incanum complex is discussed.


Asunto(s)
Alcanos/química , Hojas de la Planta/química , Solanum melongena/química , Solanum melongena/clasificación , Ceras/química , Alcoholes/química , Alcoholes/aislamiento & purificación , Alcanos/aislamiento & purificación , Biomarcadores/análisis , Análisis por Conglomerados , Ácidos Grasos/química , Ácidos Grasos/aislamiento & purificación , Variación Genética , Especificidad de la Especie , Ceras/aislamiento & purificación
2.
Pharmazie ; 58(8): 590-2, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12967041

RESUMEN

In order to check the possibility of producing secondary metabolites, in vitro cultures of A. visnaga callus were established. The best growth of A. visnaga callus was obtained on Murashige and Skoog medium (MS) containing 6-benzyladenine (BA) and alpha-naphtaleneacetic acid (NAA). The study was concentrated on the induction of production of secondary metabolites by exposing callus to abiotic elicitors: benzo(1,2,3)-thiadiazole-7-carbothionic acid S-methyl ester (BION) and a suspension of silica (SiO2) and biotic elicitors: autoclaved lysates of Enterobacter sakazaki and scleroglucan. GC analysis indicated that not-elicited callus of A. visnaga grown in darkness accumulated 2 times more visnagin than the one which was grown under a 16-h photoperiod. The highest accumulation of visnagin was observed in the callus culture elicited with scleroglucan or BION. Scleroglucan induced also the accumulation of khellin in A. visnaga callus. The presented work shows that biosynthesis of pharmacologically important secondary metabolites in A. visnaga cultures could be stimulated by application of elicitors.


Asunto(s)
Ammi/metabolismo , Cromonas/metabolismo , Furanos/metabolismo , Alcadienos/farmacología , Ammi/efectos de los fármacos , Células Cultivadas , Cromatografía de Gases , Medios de Cultivo , Enterobacter/química , Glucanos/farmacología , Luz , Fotoperiodo , Polímeros/farmacología , Dióxido de Silicio/farmacología , Estimulación Química
3.
Plant Sci ; 160(2): 259-264, 2001 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-11164597

RESUMEN

Axenically grown Ammi majus plantlets were inoculated with seven different Agrobacterium rhizogenes strains. Hairy root lines were established only after inoculation with the two agropine strains: A4 and LBA9402. The growth rate of hairy root cultures was about thirty times faster than that of callus and cell suspension cultures. Polymerase chain reaction with primers for the genes rolB and rolC confirmed the integration of the T-DNA fragment of Ri plasmid of A. rhizogenes to the genome of hairy roots obtained after transformation by both Agrobacterium strains. The furanocoumarins (psoralen, xanthotoxine, bergapten and imperatorin) usually found in seeds of A. majus were not detected in callus, cell suspension and hairy root cultures using Gas chromatography-mass spectrometry (GC-MS). However, umbelliferone, a precursor of furanocoumarins, was detected in callus, cell suspension and hairy root cultures. The umbelliferone content in extracts of hairy root cultures, obtained after transformation by A4, was similar to that determined in A. majus seeds (19 µg/g DW) and higher than those obtained for cell suspension and callus cultures (2 and 9 µg/g DW, respectively).

4.
Wiad Parazytol ; 47(4): 763-8, 2001.
Artículo en Polaco | MEDLINE | ID: mdl-16886423

RESUMEN

Five free fatty acids (FFA): C16:0, C18:0, C18:1, C18:2 and C18:3 were introduced into culture media in order to investigate differential development of pathogenic fungus Conidiobolus coronatus as a function of FFA concentration. All tested FFA showed fungistatic action inhibiting hyphae growth and sporulation. Fungal colonies grown in the presence of FFA showed decreased virulence.


Asunto(s)
Conidiobolus/efectos de los fármacos , Conidiobolus/patogenicidad , Ácidos Grasos no Esterificados/farmacología , Conidiobolus/crecimiento & desarrollo , Ácidos Grasos no Esterificados/química , Ácidos Grasos no Esterificados/clasificación , Virulencia/efectos de los fármacos
5.
Carbohydr Res ; 325(1): 16-29, 2000 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-10741824

RESUMEN

The kinetics of the acetolysis and accompanying anomerization of methyl 2,3,4,6-tetra-O-acetyl-alpha- and -beta-D-mannopyranosides at different concentrations of sulfuric acid in acetic anhydride-acetic acid mixtures were studied. The progress of the reactions was followed by gas chromatography, and the rate constants of the partial reactions were calculated on the basis of the time-dependent product distribution obtained. The mechanisms of the reactions involved are discussed. The involvement of unstable ionic intermediates is taken into account in the evaluation of the kinetic results, and simplified and extended models are used in the mathematical treatment of the results. A fourth-order Runge-Kutta algorithm is used to calculate rate constants. Acetolysis was found to be faster for mannosides than for glucosides relative to their anomerization. The beta-mannopyranoside prefers endocyclic CO-bond rupture, while in the alpha anomer the endocyclic and exocyclic cleavages are comparatively rapid.


Asunto(s)
Metilmanósidos/química , Acetatos/química , Algoritmos , Conformación de Carbohidratos , Cromatografía de Gases , Cinética , Metilglucósidos/química , Ácidos Sulfúricos/química
6.
FEMS Immunol Med Microbiol ; 21(4): 243-52, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9752996

RESUMEN

Lipopolysaccharide (LPS) of Salmonella haarlem was hydrolyzed and the products separated. The structure of the O-specific polysaccharide (OPS) was found from sugar and methylation analyses. Rhamnose, mannose, galactose and tyvelose were detected and their linkage modes were established. The structure was confirmed by 1H, homonuclear and heteronuclear correlations and 13C NMR spectra. Anomeric configurations were assigned by chromium trioxide oxidation and proton coupled 13C spectra. Sugar sequence was established from specific carbon shift data and nuclear Overhauser effect spectroscopy. The repeating unit structure of S. haarlem OPS as --> 3)-alpha-D-Galp-(1 --> 6)-[alpha-Tyvp-(1 --> 3)]-beta-D-Manp-(1 --> 4)-alpha-L-Rhap was estimated. No structural heterogeneity of the antigen was found.


Asunto(s)
Epítopos de Linfocito B/química , Antígenos O/química , Salmonella/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Epítopos de Linfocito B/inmunología , Datos de Secuencia Molecular , Antígenos O/inmunología , Salmonella/inmunología
7.
FEMS Immunol Med Microbiol ; 21(4): 253-9, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9752997

RESUMEN

Lipopolysaccharide of Salmonella haarlem was hydrolyzed and the products separated. Native O-polysaccharide antigen was oxidised with sodium periodate followed by reduction with sodium borohydride. Native and chemically modified antigens were the subject of immunochemical studies. Monoclonal antibodies against S. haarlem and polyclonal rabbit antisera against S. haarlem, S. typhi and S. anatum bacteria were produced. The serological relationship between the lipopolysaccharide of Salmonella bacteria belonging to the two different groups D2 and E1 was demonstrated using haemagglutination reactions, inhibition of haemagglutination and immunoblotting. Cross-reactions were observed in haemagglutination reactions and in immunoblotting between antisera to S. haarlem, S. typhi and S. anatum. Factors 3,9,46 were found in the S. haarlem strain and the sugar composition for the epitopes of each factor was determined.


Asunto(s)
Epítopos de Linfocito B/inmunología , Antígenos O/inmunología , Salmonella/inmunología , Animales , Secuencia de Carbohidratos , Epítopos de Linfocito B/química , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Antígenos O/química , Conejos
8.
J Chem Ecol ; 20(9): 2197-212, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24242801

RESUMEN

Branched hydrocarbons were identified in the lipids ofLeptinotarsa decemlineata Say andTribolium destructor by gas chromatography, ordinary electron impact mass spectrometry, and linked, scanned, daughterion monitoring. This methodology allowed us to revise our earlier results based only on GC-MS data confirming the existence of only monomethyl-, dimethyl-, and trimethylalkanes in the hydrocarbons ofL. decemlineata Say. The hydrocarbons fromTribolium destructor consist ofn-alkanes, 3-methylalkanes, internally branched monomethylalkanes and dimethylalkanes. Daughter-ion monitoring can be particularly important for distinguishing between incidentally overlapped GC peaks of hydrocarbons from different series. A trace, for example, of dimethylalkane coeluating withn-alkane was easily identified in GC peak of hydrocarbon mixture ofT. destructor. Link scans confirmed also molecular weights for the compounds without molecular ions in the mass spectra. Structural assignment of the compounds were verified by comparison of the experimental and calculated values of the GC retention Kovats indexes (KI).

9.
Acta Pol Pharm ; 49(4): 35-42, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-16092433

RESUMEN

Hot water extracts of Saccharomyces cerevisiae Meyen T-411 strain provided the A and B polysaccharide fractions by alcohol precipitation. Both fractions revealed marked mitostatic and, or mitodepressive activities in Allium test. The fractions were purified with DEAE-Sephadex A-25 column what resulted in obtaining of the A1-A5 and the B1-B5 subfractions. For the fractions and subfractions the elemental, sugar and amino acid analyses were carried out. Weight averaged molecular weights Mw of the A1 and B1 subfractions were estimated. Purified the A1-A5 and B1-B5 subfractions were again evaluated in Allium test but their activities markedly declined.


Asunto(s)
Mitosis/efectos de los fármacos , Polisacáridos/farmacología , Saccharomyces cerevisiae/química , Polisacáridos/aislamiento & purificación
10.
Carbohydr Res ; 214(1): 107-13, 1991 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-1954624

RESUMEN

The acidic polysaccharide from the seed-coat mucilage of Hyptis suaveolens is a highly branched L-fuco-4-O-methyl-D-glucurono-D-xylan for which a structure is proposed having a 4-linked beta-D-xylan backbone carrying side chains of single 4-O-methyl-alpha-D-glucuronic acid residues at O-2 and 2-O-L-fucopyranosyl-D-xylopyranose units at O-3. The structural analysis involves base-catalyzed beta-elimination of uronic acid residues from the methylated glycan followed by degradation using a modified Svensson oxidation-elimination sequence.


Asunto(s)
Plantas/química , Xilanos/aislamiento & purificación , Secuencia de Carbohidratos , Datos de Secuencia Molecular , Estructura Molecular , Xilanos/química
11.
Carbohydr Res ; 214(1): 95-105, 1991 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-1954635

RESUMEN

In a modification of the Svensson degradation, otherwise permethylated glycopyranosid-2-uloses bearing 4-O-glycosyl substituents are formed by the Swern oxidation. Base-catalyzed elimination on treatment with triethylamine then gives 4-deoxy-3-O-methylglyc-3-enopyranosid-2-ulose-terminat ed oligosaccharides with liberation of glycosyl substituents as reducing sugars but without further degradation. Mild acid hydrolysis results in removal of the unsaturated sugar residues so that the overall depolymerization occurs with net loss only of the initially oxidized sugar residue.


Asunto(s)
Oligosacáridos/química , Secuencia de Carbohidratos , Metilación , Datos de Secuencia Molecular , Oligosacáridos/síntesis química , Oxidación-Reducción , Polisacáridos/química
14.
J Chromatogr ; 126: 535-45, 1976 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-977695

RESUMEN

An analytical procedure for the qualitative and quantitative analysis of human lens tissue for polyol and aldose content is described. Profile samples are obtained by direct derivatization of lyophilized lenses. The components are analyzed as per-O-acetylpolyols (from the polyols) and per-O-acetylaldononitriles (from the aldoses). This procedure converts each component into a single derivative and terminal dissymmetry for each aldose is retained. The derivatives form in quantitative yield, give good chromatographic peaks, are thermally stable and readily volatilized. They are not subject to adsorption on gas chromatographic columns and are suitable for both qualitative and quantitative analytical studies. Six non-cataractous lenses and fourteen lenses from patients with senile cataract (in seven instances complicated by diabetic pathology) were analyzed. Thermostable borosilicate glass open-tubular capillary columns, coated with the nonpolar phase SE-30, and containing dispersed particles of silanized silicic acid, were used for the gas chromatographic separations. The results are discussed in relation to what is known from earlier studies of human and animal cataracts. A gas chromatographic method for determining the polyol and aldose excretion levels of controlled diabetics is also reported along with a typical metabolic profile.


Asunto(s)
Catarata/metabolismo , Cromatografía de Gases , Cristalino/análisis , Alcoholes del Azúcar/análisis , Diabetes Mellitus/metabolismo , Galactosa/análisis , Glucosa/análisis , Humanos , Inositol/análisis , Xilosa/análisis
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