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1.
Food Chem ; 213: 163-168, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27451168

RESUMO

Many plant derived commodities contain traces of toxic pyrrolizidine alkaloids (PAs). The main source of these contaminations seems to be the accidental co-harvest of PA-containing weeds. Yet, based on the insights of the newly described phenomenon of the horizontal transfer of natural products, it is very likely that the PA-contaminations may also be due to an uptake of the alkaloids from the soil, previously being leached out from rotting PA-plants. The transfer of PAs was investigated using various herbs, which had been mulched with dried plant material from Senecio jacobaea. All of the acceptor plants exhibited marked concentrations of PAs. The extent and the composition of the imported PAs was dependent on the acceptor plant species. These results demonstrate that PAs indeed are leached out from dried Senecio material into the soil and confirm their uptake by the roots of the acceptor plants and the translocation into the leaves.


Assuntos
Contaminação de Medicamentos , Compostos Fitoquímicos/análise , Plantas Daninhas/química , Alcaloides de Pirrolizidina/análise , Poluentes do Solo/análise , Folhas de Planta/química , Raízes de Plantas/química , Senécio/química
2.
J Agric Food Chem ; 54(6): 1970-4, 2006 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-16536563

RESUMO

In this study, a methodological approach for an effective and reliable quality control of Chinese star anise (Illicium verum Hook. F.) is developed and validated. A combined method of TLC and HPLC-MS/MS was used for differentiation of various Illicium species, especially Chinese and Japanese star anise. Species can be distinguished by their TLC flavonoid pattern. A sensitive and selective HPLC/ESI-MS/MS method was developed for the detection and quantification of lower admixtures of I. anisatum and of further toxic Illicium species at a low concentration range using the sesquiterpene lactone anisatin as a marker. The proposed assay includes a solid-phase extraction cleanup procedure with a high recovery (>90%). Chromatographic separation of anisatin was carried out on a C18 column, followed by MS detection using ESI in negative mode. The precursor/product ion transitions m/z 327 --> 127 (quantifier) and m/z 327 --> 297 (qualifier) were monitored. Statistical evaluation of this multireaction-monitoring procedure reveals good linearity and intra- and interday precision. The limits of detection and quantification are 1.2 and 3.9 microg/kg, respectively.


Assuntos
Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Illicium/química , Illicium/classificação , Espectrometria de Massas , Flavonoides/análise , Lactonas/análise , Controle de Qualidade , Sesquiterpenos/análise , Compostos de Espiro/análise
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