Linked Life Data

15335034

Source:http://linkedlifedata.com/resource/pubmed/id/15335034

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7-8
pubmed:dateCreated
2004-8-31
pubmed:abstractText
Flavonoids are natural compounds in medicinal herbs and posses several biological activities important in plant drug design. Especially strong antioxidant effects play an important role against radical oxidative stress causing pathological processes, such as arteriosclerosis or cancer. The aim of this work was to investigate unknown analytes found in sorrel leaf (Rumex acetosa) extracts in order to discover new leading compounds to enable quality control in phytopharmaceuticals made thereof. Therefore compounds of interest were separated after methanolic extraction by reversed-phase liquid chromatography (RP-LC) employing silica-C18 as stationary phase using gradient elution with water (10 mM H3PO4) and acetonitrile as mobile phase. Structural elucidation was carried out by diode array, fluorescence, and mass spectroscopic detection. Photodiode-array detection allowed the extraction of UV-absorbance spectra from the peaks of interest. Absorbance maxima were found at 203 and 279 nm with a shoulder at 230 nm. Additionally fluorescence emission and excitation spectra were recorded from the analytes using a fluorescence detector (FLD) after stop flow (lambdaex = 279 nm, lambdaem = 307 nm). The chromatographic reversed-phase system was coupled to an ion-trap mass spectrometer (LC-MS) by using an electrospray ionization interface (ESI). After optimization processes the separation was carried out using an ammonium acetate buffer at pH 5.5. Mass spectrometric detection turned out to be more sensitive in negative mode. Collisionally induced dissociation (CID) was used to obtain fragment ions of structural relevance (LC-MS/MS). Finally, compounds of interest coming from sorrel leaf (Rumex acetosa) eluting at low acetonitrile concentrations were confirmed to be catechin and epicatechin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1615-9306
pubmed:author
pubmed:issnType
Print
pubmed:volume
27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
524-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Structural elucidation of catechin and epicatechin in sorrel leaf extracts using liquid-chromatography coupled to diode array-, fluorescence-, and mass spectrometric detection.
pubmed:affiliation
Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University Innsbruck, Innrain 52a, 6020 Innsbruck, Austria.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't