The analysis of pyrrolizidine alkaloids in Jacobaea vulgaris; a comparison of extraction and detection methods

TY - JOUR

T1 - The analysis of pyrrolizidine alkaloids in Jacobaea vulgaris; a comparison of extraction and detection methods

AU - Joosten, L.

AU - Mulder, P.P.J.

AU - Vrieling, K.

AU - Van Veen, J.A.

AU - Klinkhamer, P.G.L.

N1 - Reporting year: 2010 Metis note: 4760;CTE; ME; file:///L:\EndnoteDatabases\NIOOPUB\pdfs\PDFS2010\Joosten_ea_4760.pdf

PY - 2010

Y1 - 2010

N2 - Introduction - Pyrrolizidine alkaloids (PAs) serve an important function in plant defence. Objective - To compare different extraction methods and detection techniques, namely gas chromatography with nitrogen phosphorus detection (GC-NPD) and liquid chromatography tandem mass spectrometry (LC-MS/MS) with quadrupole analysers for analysing PAs in Jacobaea vulgaris. Methodology - Both formic acid and sulfuric acid were tested for PA extraction from dry plant material. For GC-NPD, reduction is required to transform PA N-oxides into tertiary amines. Zinc and sodium metabisulfite were compared as reducing agents. Results - The lowest PA concentration measured with GC-NPD was approximately 0.03 mg/g and with LC-MS/MS 0.002 mg/g. The detection of major PAs by both techniques was comparable but a number of minor PAs were not detected by GC-NPD. With the LC-MS/MS procedure higher concentrations were found in plant extracts, indicating that losses may have occurred during the sample preparation for the GC-NPD method. Zinc proved a more effective reducing agent than sodium metabisulfite. The sample preparation Conclusions - In terms of sensitivity and discrimination, formic acid extraction in combination with LC-MS/MS detection is the method of choice for analysing PAs (both free and N-oxides forms) in plant material.

AB - Introduction - Pyrrolizidine alkaloids (PAs) serve an important function in plant defence. Objective - To compare different extraction methods and detection techniques, namely gas chromatography with nitrogen phosphorus detection (GC-NPD) and liquid chromatography tandem mass spectrometry (LC-MS/MS) with quadrupole analysers for analysing PAs in Jacobaea vulgaris. Methodology - Both formic acid and sulfuric acid were tested for PA extraction from dry plant material. For GC-NPD, reduction is required to transform PA N-oxides into tertiary amines. Zinc and sodium metabisulfite were compared as reducing agents. Results - The lowest PA concentration measured with GC-NPD was approximately 0.03 mg/g and with LC-MS/MS 0.002 mg/g. The detection of major PAs by both techniques was comparable but a number of minor PAs were not detected by GC-NPD. With the LC-MS/MS procedure higher concentrations were found in plant extracts, indicating that losses may have occurred during the sample preparation for the GC-NPD method. Zinc proved a more effective reducing agent than sodium metabisulfite. The sample preparation Conclusions - In terms of sensitivity and discrimination, formic acid extraction in combination with LC-MS/MS detection is the method of choice for analysing PAs (both free and N-oxides forms) in plant material.

U2 - 10.1002/pca.1183

DO - 10.1002/pca.1183

M3 - Article

SN - 0958-0344

VL - 21

SP - 197

EP - 204

JO - Phytochemical Analysis

JF - Phytochemical Analysis

IS - 2

ER -