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1.
Talanta ; 54(4): 567-74, 2001 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-18968278

RESUMO

Four digestion procedures for microwave dissolution of soils and sediments are investigated. Accurate results (accuracy better than 10%) for lanthanides, Be, Bi, Te, Th, U and Y are obtained only after an overnight stay with a mixture of 2 ml 48% HF and 2 ml 65% HNO(3) and afterwards stepwise microwave digestion with 1 ml 48% HF and 10 ml 5% H(3)BO(3). Only As is not be to be determined by this procedure due to significant interferences from Eu, Nd and Sm. For all other elements, accurate results are obtained by all four procedures.

2.
Sci Total Environ ; 280(1-3): 85-91, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11763275

RESUMO

The concentrations of lanthanoids, Be, Bi,Ga, Te, Tl, Th and U have been determined using ICP-MS for 100 standardized samples of poplar leaves collected from the territory of Bulgaria. The investigated elements are log-normally distributed on the territory. Using cluster analysis of the analytical data the samples were grouped according soil type on which the plants are growing.


Assuntos
Elementos da Série dos Lantanídeos/análise , Salicaceae , Poluentes do Solo/análise , Bulgária , Monitoramento Ambiental , Folhas de Planta/química , Distribuição Tecidual
3.
Fresenius J Anal Chem ; 366(3): 316-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11225681

RESUMO

A sensitive method for the determination of phytochelatins in plant matrices by pre-column derivatization with monobromobimane (mBrB) and high-performance liquid chromatography (HPLC) on reversed phases and fluorescence-detection has been developed and applied to cucumber sprouts (Cucumis sativus) treated with cadmium and to the water moss Fontinalis antipyretica (Cd in environmentally-relevant concentrations). Whereas phytochelatins were found in the Cd-treated sprouts, no phytochelatins were detected in Fontinalis anitipyretica.


Assuntos
Bryopsida/química , Cucumis sativus/química , Metaloproteínas/análise , Proteínas de Plantas/análise , Plantas/química , Cromatografia Líquida de Alta Pressão/métodos , Glutationa , Metais/análise , Fitoquelatinas , Controle de Qualidade , Reprodutibilidade dos Testes , Espectrometria de Fluorescência/métodos , Espectrometria de Fluorescência/normas , Oligoelementos/análise
4.
Fresenius J Anal Chem ; 368(7): 664-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11227545

RESUMO

The determination of the residual water content by thermal methods and especially by Karl Fischer titration in a candidate reference material of the European Commission (candidate CRM 679 cabbage powder) is described and discussed.


Assuntos
Brassica/química , Monitoramento Ambiental , Liofilização , Folhas de Planta/química , Pós , Padrões de Referência , Água/análise
5.
Planta Med ; 58(1): 94-8, 1992 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-1620749

RESUMO

Four new main saponins (canadensis-saponins 5-8) (compounds 5-8) were isolated from Solidago canadensis L. (Asteraceae). Using GC/MS, FAB-MS, and mainly 2D-NMR techniques their structures were identified as 3-O-[beta-D-glucopyranosyl(1----3)-beta-D- glucopyranosyl]-28-O-[beta-D-galactopyranosyl(1----2)-alpha-L- rhamnopyranosyl-(1----3)-beta-D-xylopyranosyl-(1----4)-[beta-D- xylopyranosyl-(1----3)]-alpha-L-rhamnopyranosyl-(1----2)-[beta-D-apio -D- furanosyl-(1----3)]-beta-D-6-deoxyglucopyranosyl-(1----)]-bayog enin(5),3-O- [beta-D-glucopyranosyl-(1----3)-beta-D-glucopyranosyl]-28-O-[beta-D- galactopyranosyl-(1----2)-alpha-L-rhamnopyranosyl-(1----3)-beta-D- xylopyranosyl-(1----4)-[beta-D-xylopyranosyl-(1----3)]-alpha-L- rhamnopyranosyl-(1----2)-[beta-D-apio-D-furanosyl-(1----3)]- arabinopyranosyl-(1----)]bayogenin(6),3-O-[beta-D-glucopy ran osyl-(1----3)- beta-D-glucopyranosyl]-28-O-[beta-D-galactopyranosyl-(1----2)- alpha-L-rhamnopyranosyl-(1----3)-beta-D-xylopyranosyl-(1----4)-[beta-D- xylopyranosyl-(1----3)]-alpha-L-rhamnopyranosyl-(1----2)-[alpha-L- rhamnopyranosyl-(1----3)]-beta-D-6-deoxyglucopyranosyl-(1----)]-++ +bayogenin (7), and 3-O-[beta-D-glucopyranosyl-(1----3)-beta-D-glucopyranosyl]-28-[O- beta-D-galactopyranosyl-(1----2)-alpha-L-rhamnopyranosyl-(1----3)-beta-D - xylopyranosyl-(1----4)-[beta-D-xylopyranosyl-(1----3)]-alpha-L- rhamnopyranosyl-(1----2)-[alpha-L-rhamnopyranosyl-(1----3)]arabinopyr anosyl - (1----)[-bayogenin (8).


Assuntos
Plantas/química , Saponinas/isolamento & purificação , Sequência de Carboidratos , Dados de Sequência Molecular , Estrutura Molecular , Saponinas/química
6.
Planta Med ; 57(5): 444-6, 1991 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-1798798

RESUMO

From the aerial parts of Achillea setacea W. & K. (Asteraceae) the main sesquiterpenes were isolated. Their structures were determined by means of 2D-NMR and MS as 11,13-dehydrodeacetylmatricarin (1) (= 14-deoxylactucin), rupicolin A (2), and rupicolin B (3). These are the first compounds with an alpha-methylene-gamma-lactone structure isolated from a species belonging to the Achillea millefolium aggregate. Achillicin, achillin, 8-hydroxyachillin, 8-acetoxyachillin, and matricin could not be detected in A. setacea. For both rupicolin B and 11,13-dehydrodeacetylmatricarin an anti-inflammatory activity was found in the croton oil ear test.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Lactonas/farmacologia , Plantas/química , Sesquiterpenos/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Lactonas/química , Lactonas/isolamento & purificação , Estrutura Molecular , Forbóis , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação
7.
Phytochemistry ; 30(5): 1629-33, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1367338

RESUMO

Four new bisdesmosidic saponins each containing eight carbohydrate units were isolated from Solidago canadensis. GC, GC-MS, FABMS analysis and mainly the use of 2D NMR techniques allowed their identification as bayogeninglycosides (canadensissaponins 1-4) 3-O- [beta-D-glucopyranosyl-(1----3)-beta-D-glucopyranosyl]-28-O-[alpha-L- rhamnopyranosyl-(1----3)-beta-D-xylopyranosyl-(1----4)-[beta-D- xylopyranosyl-(1----3)]-alpha-L-rhamnopyranosyl-(1----2)-[beta-D- apio-D-furanosyl-(1----3)]-beta-D-6-deoxyglucopyranosyl- (1----]-bayogenin; -(1----2)-[beta-D-apio-D-furanosyl-(1----3)]-ara- binopyranosyl-(1----]-bayogenin; -[alpha-L-rhamnopyranosyl-(1----3)]-beta- D-6-deoxyglucopyranosyl-(1----]-bayogenin and - [alpha-L-rhamnopyranosyl- (1----3)]-arabinopyranosyl-(1----]-bayogenin.


Assuntos
Plantas Medicinais/análise , Saponinas/isolamento & purificação , Sequência de Carboidratos , Dados de Sequência Molecular , Estrutura Molecular , Saponinas/química
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